Functions (Edexcel A Level Maths: Pure): Exam Questions

Exam code: 9MA0

4 hours45 questions
1
4 marks

State whether the following mappings are one-to-one or many-to-one:

(i) straight f colon space x rightwards arrow from bar 4 x minus 2

(ii) straight f colon space x rightwards arrow from bar x squared

(iii) straight f colon space x rightwards arrow from bar x over 4

(iv) straight f colon space x rightwards arrow from bar square root of x

2
3 marks

Find the range for the following functions, given their domains:

(i) straight f colon space x rightwards arrow from bar straight e to the power of x space space space space space space space space space space x element of straight real numbers 

(ii) straight f colon space x rightwards arrow from bar x squared plus 1 space space space space space space space space space space x element of straight real numbers

(iii) straight f colon space x rightwards arrow from bar 1 over x space space space space space space space space space space x element of straight real numbers comma space x not equal to 0 

3a
1 mark

The function straight f is defined by

straight f left parenthesis x right parenthesis equals x squared minus 4 

If the domain of straight f is x greater or equal than 0, find the range of straight f.

3b
1 mark

If the domain of straight f is x less or equal than 0, find the range of straight f.

4
2 marks

The function straight f open parentheses x close parentheses is defined as

straight f left parenthesis x right parenthesis equals x squared minus 9 

(i) If the domain of straight f is x greater or equal than 3, find the range of straight f.

(ii) If the domain of straight f is x greater or equal than 0, find the range of straight f.

5a
2 marks

The functions straight f open parentheses x close parentheses and straight g open parentheses x close parentheses are defined as follows:

 straight f left parenthesis x right parenthesis equals 3 x plus 5

straight g left parenthesis x right parenthesis equals negative 2 x

Find and simplify expressions for

(i) fg open parentheses x close parentheses

(ii) gf open parentheses x close parentheses

 

5b
2 marks

Solve the equation

straight f open parentheses x close parentheses equals straight g open parentheses x close parentheses

6a
2 marks

The function straight f open parentheses x close parentheses is defined by

 straight f left parenthesis x right parenthesis equals 3 x squared plus 1 space space space space space space space space space space x greater or equal than 0

Find an algebraic expression for the inverse function, straight f to the power of negative 1 end exponent open parentheses x close parentheses.

6b
2 marks

Find the domain and range of straight f to the power of negative 1 end exponent open parentheses x close parentheses.

7a
2 marks

Solve the equation 

vertical line 6 minus 2 x vertical line equals space 4

7b
2 marks

On the same axes, sketch the graphs of y equals vertical line 6 minus 2 x vertical line and y equals 4.

Label clearly the coordinates of

  • any points of intersection between the two graphs

  • any points where the graphs meet the coordinate axes

7c
3 marks

Consider the graphs of y equals vertical line 6 minus 2 x vertical line and y equals k, where k is a constant.

Find the values of k for which the graphs have

(i) no points of intersection,
(ii) exactly one point of intersection,
(iii) two points of intersection.

8a
1 mark

The functions straight f and straight g are defined as follows:

 straight f left parenthesis x right parenthesis equals x squared space space space space space space space space space space space space space space space space space space space x element of straight real numbers

straight g left parenthesis x right parenthesis equals 4 x minus 3 space space space space space space space space space space space space space space space space space space space x element of straight real numbers

Find the range of straight f.

8b
4 marks

Find

(i)      fg open parentheses x close parentheses

(ii) gf open parentheses x close parentheses

Give your answers in the form a x squared plus b x plus c where a, b and c are constants to be found.

8c
2 marks

Solve the equation

straight f open parentheses x close parentheses equals straight g open parentheses x close parentheses

9
2 marks

Solve the equation 

 vertical line 4 x plus 2 vertical line equals 5

10a
1 mark

Find the largest possible domain for the function

 straight f left parenthesis x right parenthesis equals 2 over x

10b
1 mark

Using the domain in part (a), sketch the graph of y equals straight f open parentheses x close parentheses.

10c
1 mark

Find the range of straight f open parentheses x close parentheses.

11
1 mark

The graph of y equals straight f open parentheses x close parentheses is shown below.

The dotted line has the equation y equals x

2-8-m-q5-edexcel-al-maths-pure

On the diagram, sketch the graph of y equals straight f to the power of negative 1 end exponent open parentheses x close parentheses.

12a
2 marks

The function straight f open parentheses x close parentheses is defined as

straight f left parenthesis x right parenthesis equals x to the power of 2 space end exponent minus 8 x minus 20 space space space space space space space space space space x element of straight real numbers

Sketch the curve y equals straight f open parentheses x close parentheses, labelling the coordinates of any points where the curve meets the coordinate axes.

12b
1 mark

The minimum point on the curve y equals straight f open parentheses x close parentheses has an x -coordinate of 4.

Find the range of straight f open parentheses x close parentheses.

1a
1 mark

The functions straight f and straight g are defined by

table row cell straight f open parentheses x close parentheses equals 7 minus 2 x squared end cell blank cell x element of straight real numbers end cell blank blank row cell straight g open parentheses x close parentheses equals fraction numerator 3 x over denominator 5 x minus 1 end fraction end cell blank cell x element of straight real numbers end cell blank cell x not equal to 1 fifth end cell end table

State the range of straight f

1b
1 mark

Find gf open parentheses 1.8 close parentheses

1c
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2 marks

Find straight g to the power of negative 1 end exponent open parentheses x close parentheses

2
4 marks

In this question you must show all stages of your working.

Solutions relying entirely on calculator technology are not acceptable.

Graph of the equation y = |3 - 2x|, forming a V shape that touches the x-axis at one point where x>0.
Figure 1

Figure 1 shows a sketch of the graph with equation y equals open vertical bar 3 minus 2 x close vertical bar

Solve

open vertical bar 3 minus 2 x close vertical bar equals 7 plus x

3
1 mark

The point P left parenthesis negative 2 comma negative 5 right parenthesis lies on the curve with equation y equals straight f left parenthesis x right parenthesis comma space space x element of straight real numbers

Find the point to which P is mapped, when the curve with equation y equals straight f left parenthesis x right parenthesis is transformed to the curve with equation

y equals vertical line straight f left parenthesis x right parenthesis vertical line

4
3 marks

(i) Sketch the graph of y equals open vertical bar x close vertical bar plus 3.

(ii) Explain why open vertical bar x close vertical bar plus 3 greater or equal than open vertical bar x plus 3 close vertical bar for all real values of x.

5a
3 marks

The function straight f open parentheses x close parentheses is defined as

straight f left parenthesis x right parenthesis equals x to the power of 2 space end exponent plus 2 x minus 3 space space space space space space space space space space x element of straight real numbers

Sketch the curve y equals straight f open parentheses x close parentheses, labelling the coordinates of any points where the curve meets the coordinate axes.

Find and label the coordinates of the turning point on your sketch.

5b
1 mark

Find the range of straight f.

6
3 marks

Find the largest possible domains of the following functions:

(i) straight f colon space x rightwards arrow from bar square root of x

(ii) straight f colon space x rightwards arrow from bar ln left parenthesis x minus 2 right parenthesis

(iii) straight f colon space x rightwards arrow from bar arcsin space x

7a
2 marks

On the same axes, sketch the graphs of y equals straight f open parentheses x close parentheses and y equals vertical line straight g left parenthesis x right parenthesis vertical line where

straight f left parenthesis x right parenthesis equals left parenthesis x plus 2 right parenthesis squared space space space space space space space space space space x element of straight real numbers

 straight g left parenthesis x right parenthesis equals 2 x plus 4 space space space space space space space space space space space x element of straight real numbers

Label the points at which the graphs meet the coordinate axes.

7b
3 marks

Solve the equation 

open parentheses x plus 2 close parentheses squared equals vertical line 2 x plus 4 vertical line

8a
1 mark

The function straight f is defined as

straight f colon space x space rightwards arrow from bar space fraction numerator x squared plus 1 over denominator x squared end fraction space space space space space space space space space space x element of straight real numbers comma space x not equal to 0

 Show that straight f can be written in the form

 straight f colon space x space rightwards arrow from bar space a space plus space b over x squared space space space space space space space space space space x element of straight real numbers comma space x not equal to 0

where a and b are constants to be found.

8b
1 mark

Explain why the inverse of straight f does not exist.

8c
4 marks

The domain of straight f is changed to x greater than 0.

 Find straight f to the power of negative 1 end exponent open parentheses x close parentheses and state its domain and range.

9
4 marks

State whether the following mappings are one-to-one or many-to-one:

(i)       straight f colon space x space rightwards arrow from bar space 2 minus x cubed

(ii) straight f colon space x space rightwards arrow from bar space sin space x

(iii)     straight f colon space x space rightwards arrow from bar space 1 over x squared

(iv) straight f colon space x space rightwards arrow from bar space ln space x

10a
4 marks

The functions straight f open parentheses x close parentheses and straight g open parentheses x close parentheses are defined as follows:

straight f left parenthesis x right parenthesis equals 1 half left parenthesis 4 x minus 3 right parenthesis space space space space space space space space space space space space x element of straight real numbers

straight g left parenthesis x right parenthesis equals 0.5 x plus 0.75 space space space space space space space space space space space x element of straight real numbers

Find and simplify

(i) fg left parenthesis x right parenthesis

(ii) gf left parenthesis x right parenthesis

10b
3 marks

Explain why straight f to the power of negative 1 end exponent open parentheses x close parentheses equals straight g open parentheses x close parentheses and state the domain and range of straight f to the power of negative 1 end exponent open parentheses x close parentheses.

11a
3 marks

The functions straight f open parentheses x close parentheses and straight g open parentheses x close parentheses are defined as follows:

straight f left parenthesis x right parenthesis equals vertical line x minus 9 vertical line space space space space space space space space space space space space x element of straight real numbers

straight g left parenthesis x right parenthesis equals x squared space space space space space space space space space space space space space space space x element of straight real numbers

Sketch the graph of y equals fg open parentheses x close parentheses and label the coordinates of any points where the graph meets the coordinate axes.

11b
2 marks

Find the number of solutions to the equation

fg open parentheses x close parentheses equals k

in the cases when:

(i) k equals 5

(ii) k equals 9

11c
1 mark

Solve

fg open parentheses x close parentheses equals 0

12a
1 mark

The functions straight f and straight g are defined by:

straight f left parenthesis x right parenthesis equals 3 x squared plus 2 space space space space space space space space space space space space x element of straight real numbers

 straight g left parenthesis x right parenthesis equals 1 minus 3 x space space space space space space space space space space space space space x element of straight real numbers

Find the range of straight f.

12b
4 marks

Find expressions for

(i)  fg open parentheses x close parentheses

(ii)  gf open parentheses x close parentheses

Give your answers in the form a x squared plus b x plus c where a, b and c are constants to be found.

12c
2 marks

Solve the equation

straight f open parentheses x close parentheses equals straight g open parentheses x close parentheses plus 1

13
2 marks

The graph of y equals straight f open parentheses x close parentheses is shown below.

The dotted line has the equation y equals x

28-q5-edexcel-al-maths-pure-hard

On the diagram, sketch the graph of y equals straight f to the power of negative 1 end exponent open parentheses x close parentheses.

14a
4 marks

On the same axes, sketch the graphs of y equals vertical line straight f left parenthesis x right parenthesis vertical line  and y equals vertical line straight g left parenthesis x right parenthesis vertical line where

straight f left parenthesis x right parenthesis equals 3 x minus 1 space space space space space space space space space space space space x element of straight real numbers

straight g left parenthesis x right parenthesis equals 2 x plus 2 space space space space space space space space space space space space x element of straight real numbers

Label the coordinates of the points at which the graphs meet the coordinate axes.

14b
4 marks

Solve the equation

vertical line straight f left parenthesis x right parenthesis vertical line equals vertical line straight g left parenthesis x right parenthesis vertical line

14c
1 mark

Which of the solutions to vertical line straight f left parenthesis x right parenthesis vertical line equals vertical line straight g left parenthesis x right parenthesis vertical line is also a solution to straight f left parenthesis x right parenthesis equals straight g left parenthesis x right parenthesis?

1a
2 marks

straight g open parentheses x close parentheses equals fraction numerator 2 x plus 5 over denominator x minus 3 end fraction space space space space space x greater or equal than 5

Find gg open parentheses 5 close parentheses.

1b
1 mark

State the range of straight g.

1c
3 marks

Find straight g to the power of negative 1 end exponent open parentheses x close parentheses, stating its domain.

2a
2 marks

The function straight f is defined by

straight f open parentheses x close parentheses equals fraction numerator 8 x plus 5 over denominator 2 x plus 3 end fraction space space space space space space space space space space space space space x greater than negative 3 over 2

Find straight f to the power of negative 1 end exponent open parentheses 3 over 2 close parentheses

2b
2 marks

Show that

straight f open parentheses x close parentheses equals A plus fraction numerator B over denominator 2 x plus 3 end fraction

where A and B are constants to be found.

2c
1 mark

The function straight g is defined by

straight g open parentheses x close parentheses equals 16 minus x squared space space space space space space space space space space space space space 0 less or equal than x less or equal than 4

State the range of straight g to the power of negative 1 end exponent

2d
3 marks

Find the range of space straight f straight g to the power of negative 1 end exponent

3a
2 marks
A graph with a parabola opening upwards, vertex at the origin, labelled x-axis and y-axis. Origin is marked O, axes have arrows indicating positive direction.
Figure 4

Figure 4 shows a sketch of the graph of y equals straight g open parentheses x close parentheses, where

straight g open parentheses x close parentheses equals open curly brackets table row cell open parentheses x minus 2 close parentheses squared plus 1 end cell cell x less or equal than 2 end cell row cell 4 x minus 7 end cell cell x greater than 2 end cell end table close

Find the value of gg open parentheses 0 close parentheses.

3b
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4 marks

Find all the values of x for which

straight g open parentheses x close parentheses greater than 28

3c
1 mark

The function straight h is defined by

straight h open parentheses x close parentheses equals open parentheses x minus 2 close parentheses squared plus 1 space space space x less or equal than 2

Explain why straight h has an inverse but straight g does not.

3d
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3 marks

Solve

straight h to the power of negative 1 end exponent open parentheses x close parentheses equals negative 1 half

4a
2 marks
A V-shaped graph with its vertex at point P in the third quadrant.  The graph intersects the x-axis twice (both times to the left of the y-axis), and it intersects the y-axis once at a positive value of y. The axes are labelled x and y. The origin is marked O.
Figure 2

Figure 2 shows a sketch of the graph with equation

y space equals space 2 open vertical bar x plus 4 close vertical bar minus 5

The vertex of the graph is at the point P, shown in Figure 2.

Find the coordinates of P.

4b
2 marks

Solve the equation

3 x plus 40 equals 2 open vertical bar x plus 4 close vertical bar minus 5

4c
3 marks

A line l has equation y equals a x, where a is a constant.

Given that l intersects y equals 2 open vertical bar x plus 4 close vertical bar minus 5 at least once,

find the range of possible values of a, writing your answer in set notation.

5a
3 marks

table row cell straight f open parentheses x close parentheses equals 2 x squared plus 4 x plus 9 end cell blank cell x element of straight real numbers end cell end table

Write straight f open parentheses x close parentheses in the form a open parentheses x plus b close parentheses squared plus c, where a comma space b and c are integers to be found.

5b
3 marks

Sketch the curve with equation y equals straight f open parentheses x close parentheses showing any points of intersection with the coordinate axes and the coordinates of any turning point.

5c
2 marks

Find the range of the function

table row cell straight h open parentheses x close parentheses equals fraction numerator 21 over denominator 2 x squared plus 4 x plus 9 end fraction end cell blank cell x element of straight real numbers end cell end table

6
4 marks

Solve the equation vertical line x to the power of 2 space end exponent minus 4 vertical line equals 3 , giving your answers in exact form.

7a
4 marks

The functions straight f open parentheses x close parentheses and straight g open parentheses x close parentheses are defined by

straight f left parenthesis x right parenthesis equals straight e to the power of x minus 2 end exponent space space space space space space space space space space space space space space space space space space space space x element of straight real numbers

 straight g left parenthesis x right parenthesis equals 2 plus ln space x space space space space space space space space space space space space x greater than 0

Find and simplify expressions for

(i) fg left parenthesis x right parenthesis

(ii) gf left parenthesis x right parenthesis

7b
3 marks

Explain why straight f to the power of negative 1 end exponent open parentheses x close parentheses equals straight g open parentheses x close parentheses and state the domain and range of straight f to the power of negative 1 end exponent open parentheses x close parentheses.

7c
1 mark

Describe the transformation that would map the graph of y equals straight f open parentheses x close parentheses on to the graph of y equals straight g open parentheses x close parentheses.

8a
4 marks

The functions straight f open parentheses x close parentheses and straight g open parentheses x close parentheses are defined by

straight f left parenthesis x right parenthesis equals vertical line x minus 2 vertical line minus 5 space space space space space space space space space space space space space x element of straight real numbers

straight g left parenthesis x right parenthesis equals vertical line x vertical line space space space space space space space space space space space space space space space space space space space space space space space space space space x element of straight real numbers

Sketch the graph of y equals gf open parentheses x close parentheses.

Label clearly the coordinates of any points where the graph meets the coordinate axes.

8b
2 marks

Find the number of solutions to the equation

gf open parentheses x close parentheses equals k

in the cases when:

(i) k equals 1

(ii) k equals 10

8c
4 marks

Solve the equation

gf open parentheses x close parentheses equals 2

9a
1 mark

The functions straight f and straight g are defined by

straight f left parenthesis x right parenthesis equals x squared minus 2 space space space space space space space space space space space space x element of straight real numbers

straight g left parenthesis x right parenthesis equals 1 minus 2 over x space space space space space space space space space space space x element of straight real numbers comma space x not equal to 0

Find the range of straight f.

9b
4 marks

Leaving your answers as single algebraic fractions, find expressions for

(i)   fg open parentheses x close parentheses

(ii) gf open parentheses x close parentheses

9c
3 marks

Use algebra to solve the equation

straight f open parentheses x close parentheses equals straight g open parentheses x close parentheses

10a
3 marks

On the same axes, sketch the graphs of y equals straight f open parentheses x close parentheses and y equals vertical line straight g left parenthesis x right parenthesis vertical line where

straight f left parenthesis x right parenthesis equals square root of x space space space space space space space space space space space space space space space space x greater or equal than 0

straight g left parenthesis x right parenthesis equals 2 x minus 3 space space space space space space space space space space space space x element of straight real numbers

Label the points at which the graphs meet the coordinate axes.

10b
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3 marks

Solve the equation

straight f left parenthesis x right parenthesis equals vertical line straight g left parenthesis x right parenthesis vertical line

10c
1 mark

Which (if any) of the solutions to straight f left parenthesis x right parenthesis equals vertical line straight g left parenthesis x right parenthesis vertical line are not solutions to straight f open parentheses x close parentheses equals straight g open parentheses x close parentheses?

11a
3 marks

A function is defined by

straight f left parenthesis x right parenthesis space equals a vertical line x plus p vertical line plus q space space space space space space space space space space space x element of straight real numbers

where a comma space p comma space q element of straight real numbers.

The graph of y equals straight f open parentheses x close parenthesesis shown below, where

  • A open parentheses 3 comma space 5 close parentheses is the local maximum point

  • open parentheses 0 comma space minus 7 close parentheses is the y-intercept

q7a-2-9-ib-aa-hl-further-functions-_-graphs-very-hard-dig

 

Find the values of a comma space p and q.

11b
4 marks

Solve

straight f left parenthesis x right parenthesis space equals space open vertical bar 7 space minus space 2 x close vertical bar

12
4 marks

Solve the equation 

vertical line x squared minus 9 vertical line equals 6 minus 0.25 x squared

giving your answers in exact form.

1a
2 marks

The function straight f is defined by

straight f open parentheses x close parentheses equals fraction numerator 3 x minus 7 over denominator x minus 2 end fraction space space space space space space space space x element of straight real numbers comma space space x not equal to 2

Find straight f to the power of negative 1 end exponent open parentheses 7 close parentheses.

1b
3 marks

Show that ff open parentheses x close parentheses equals fraction numerator a x plus b over denominator x minus 3 end fraction where a and b are integers to be found.

2a
4 marks
Graph of a V-shaped function with lines converging at some point on the positive x-axis.
Figure 4

Figure 4 shows a sketch of the graph with equation

y equals open vertical bar 2 x minus 3 k close vertical bar

where k is a positive constant.

Sketch the graph with equation y equals straight f open parentheses x close parentheses where

straight f left parenthesis x right parenthesis equals k minus open vertical bar 2 x minus 3 k close vertical bar

stating

  • the coordinates of the maximum point

  • the coordinates of any points where the graph cuts the coordinate axes

2b
4 marks

Find, in terms of k, the set of values of x for which

k minus open vertical bar 2 x minus 3 k close vertical bar greater than x minus k

giving your answer in set notation.

3a
1 mark

The function straight f is defined by

straight f open parentheses x close parentheses equals 3 plus square root of x minus 2 end root space space space space space space space space space space space x element of straight real numbers space space space space space space space space space x greater than 2

State the range of straight f

3b
3 marks

Find straight f to the power of negative 1 end exponent

3c
2 marks

The function straight g is defined by

straight g open parentheses x close parentheses equals fraction numerator 15 over denominator x minus 3 end fraction space space space space space space space space space space x element of straight real numbers space space space space space space space space x not equal to 3

Find gf open parentheses 6 close parentheses

3d
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2 marks

Find the exact value of the constant a for which

straight f open parentheses a squared plus 2 close parentheses equals straight g open parentheses a close parentheses

4a
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3 marks

The function straight f is defined by

straight f left parenthesis x right parenthesis equals left parenthesis x minus 3 right parenthesis squared left parenthesis x minus 4 right parenthesis squared space space space space space space space space space space space space space 2 less or equal than x less or equal than 5

Find the range of straight f.

You must show your working clearly.

4b
1 mark

The domain of straight f is changed to x less or equal than 2

Find the range of straight f.

4c
1 mark

Find a different domain of straight f that has the same range as in part (b).

5a
3 marks

The graph of y equals straight f open parentheses x close parentheses is shown in the diagram below. The dotted line has equation y equals x.

You are given that

  • y equals straight f open parentheses x close parentheses has rotational symmetry about the origin

  • For x greater than 0, the vertices of the graph have coordinates open parentheses 3 comma space 6 close parentheses, open parentheses 6 comma space 6 close parentheses and open parentheses 9 comma space 0 close parentheses

  • y equals straight f open parentheses x close parentheses does not continue for x squared greater than 81

 

2-8-vh-q5-edexcel-al-maths-pure

(i) Find the domain and range of the function straight f.

(ii) On the diagram above, sketch the reflection of y equals straight f open parentheses x close parentheses in the line y equals x and explain why this cannot be the graph of y equals straight f to the power of negative 1 end exponent open parentheses x close parentheses

5b
3 marks

(i) Find the largest restricted domain of straight f that includes the value x equals 0 such that straight f to the power of negative 1 end exponent open parentheses x close parentheses exists.

(ii) Assuming the domain of straight f in part (b)(ii) is used, find the domain and range of the function straight f to the power of negative 1 end exponent.

6a
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2 marks

The function straight f is defined by

straight f colon space x space rightwards arrow from bar square root of 25 minus x squared space end root space space space space space space space space space space space minus 5 less or equal than x less or equal than 5

Determine whether or not the inverse of straight f exists.

6b
2 marks

The domain is changed such that

  • the inverse of straight f exists

  • the graph of y equals straight f open parentheses x close parentheses lies in the first quadrant only

  • the domain of straight f is as large as possible

Find the new domain and range of straight f.

6c
4 marks

The domain of straight f is changed to negative 5 less or equal than x less or equal than 0.

Find an expression for straight f to the power of negative 1 end exponent left parenthesis x right parenthesis.

State also the domain and range of straight f to the power of negative 1 end exponent.

7a
4 marks

The functions straight f and straight g are defined by

 straight f left parenthesis x right parenthesis equals left parenthesis x minus 1 right parenthesis squared minus 4 space space space space space space space space space space space space space space space x greater or equal than 1

straight g left parenthesis x right parenthesis equals 1 plus square root of x plus 4 space end root space space space space space space space space space space space space x greater or equal than negative 4

Find and simplify expressions for

(i)  fg open parentheses x close parentheses

(ii)  gf open parentheses x close parentheses

7b
3 marks

Write down straight f to the power of negative 1 end exponent left parenthesis x right parenthesis and state its domain and range.

7c
1 mark

Describe the transformation that would map the graph of y equals straight f open parentheses x close parentheses on to the graph of y equals straight g open parentheses x close parentheses.

7d
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4 marks

Find the coordinates of the point of intersection between the curves  y equals straight f open parentheses x close parentheses and y equals straight g open parentheses x close parentheses.