Differentiation (DP IB Analysis & Approaches (AA): SL): Exam Questions

3 hours24 questions
1
3 marks

Let f\left(x\right) = -9x^{2} + 5x - 3.

Find the values of x for which f is increasing.

1a
2 marks

The equation of a curve is y = \frac{3}{2}x^{2} - 15x + 2.

Find \frac{\mathrm{d}y}{\mathrm{d}x}.

1b
4 marks

The gradient of the tangent to the curve at the point \mathrm{A} is -3.

Find

(i) the coordinates of \mathrm{A}

(ii) the equation of the tangent to the curve at \mathrm{A}. Give your answer in the form y = mx + c.

2a
1 mark

Consider the function f\left(x\right) = 3x^{7} - 12x.

Find f'\left(x\right).

2b
2 marks

Find the gradient of the graph of f at x = 0.

2c
3 marks

Find the coordinates of the points on the graph of f where the normal has a gradient of 4.

3a
3 marks

The equation of a curve is y = 4 - \frac{4}{x}.

Find the equation of the tangent to the curve at the point where x = 2. Give your answer in the form y = mx + c.

3b
3 marks

Find the coordinates of the points on the curve where the gradient is 16.

4a
3 marks

Consider the function f\left(x\right) = \frac{4}{x} + \frac{2x^{4}}{5} - \frac{2}{5}, x \neq 0.

Find

(i) f\left(2\right)

(ii) f'\left(2\right).

4b
3 marks

The line l is tangent to the graph of y = f\left(x\right) at the point where x = 2.

Find the equation of l. Give your answer in the form y = mx + c.

4c
2 marks

The graph of y = f\left(x\right) and the line l intersect again at the point \mathrm{A}.

Use your graphic display calculator to find the coordinates of \mathrm{A}.

5a
1 mark

Consider the function f\left(x\right) = x^{2} - bx + c, where b, \; c \in \mathbb{R}.

Find f'\left(x\right).

5b
2 marks

The tangent to the graph of y = f\left(x\right) at x = 2 has equation y = x - 1.

Find the value of b.

5c
3 marks

Find the value of c.

6a
2 marks

The curve with equation y = ax^{2} + bx + c has a gradient of -7 at the point \left(-1, \; 13\right) and a gradient of -3 at the point \left(1, \; 3\right).

By considering \frac{\mathrm{d}y}{\mathrm{d}x}, show that 2a + b = -3 and -2a + b = -7.

6b
1 mark

Hence find the values of a and b.

6c
2 marks

By considering a point that you know to be on the curve, find the value of c.

7a
2 marks

The curve C has equation y = 3x^{2} - 6 + \frac{4}{x}. The point \mathrm{P}\left(1, \; 1\right) lies on C.

Find \frac{\mathrm{d}y}{\mathrm{d}x}.

7b
3 marks

Show that the equation of the normal to C at \mathrm{P} is x + 2y = 3.

7c
2 marks

The normal meets the x-axis at the point \mathrm{Q}.

Find \mathrm{PQ}, giving your answer as an exact value.

8a
2 marks

The graph of the cubic function y = f\left(x\right) is shown below. Point \mathrm{A}, a local minimum, is located at the origin and point \mathrm{B}, a local maximum, sits at the point \left(4, \; 8\right).

q10-5-1-medium-ib-aa-sl

State the equations of the horizontal tangents to the curve.

8b
1 mark

Write down the value of x where the point of inflexion is located.

8c
2 marks

Find the intervals where f is decreasing.

8d
3 marks

Sketch the graph of f'\left(x\right), labelling clearly any intercepts and axis of symmetry.

9a
5 marks

The diagram below shows part of the curve with equation y = x^{3} + 11x^{2} + 35x + 25. The curve touches the x-axis at \mathrm{A} and cuts the x-axis at \mathrm{C}. The point \mathrm{A} is a local maximum point and the point \mathrm{B} is a local minimum point.

q11-5-1-medium-ib-aa-sl

Using calculus, and showing all your working, find the coordinates of \mathrm{A} and \mathrm{B}.

9b
2 marks

Show that \left(-1, \; 0\right) lies on the curve, and explain why it must be the point \mathrm{C}.

10a
2 marks

The equation of the curve C is y = \frac{1}{35}x^{5} - \frac{3}{4}x^{3} + 6x. A section of the curve C is shown on the diagram below.

ib6-ai-sl-5-1-ib-maths-medium

Find \frac{\mathrm{d}y}{\mathrm{d}x}.

10b
4 marks

There are two points, \mathrm{R} and \mathrm{S}, on the curve C at which the gradient of the normal to C is -\frac{1}{10}, where the x-coordinate of \mathrm{R} is positive.

Find the x-coordinates of \mathrm{R} and \mathrm{S}.

11a
2 marks

The equation of a curve is y = x - \frac{9}{x} + 8, for x > 0.

Find \frac{\mathrm{d}y}{\mathrm{d}x}.

11b
3 marks

The gradient of the tangent to the curve at the point \mathrm{A} is 2.

Find the coordinates of \mathrm{A}.

11c
3 marks

Find the equation of the normal to the curve at \mathrm{A}. Give your answer in the form ax + by + d = 0, where a, b and d are integers.

12
5 marks

Let f\left(x\right) = ax^{2} + 2x + 9. The gradient of the tangent to the graph of f at the point \left(-2, \; b\right) is 14.

Find the value of a and the value of b.

13a
2 marks

The diagram below shows part of the graph of the function y = f\left(x\right), where f\left(x\right) = \frac{4}{x} + x^{2} - 4, x > 0.

q5-5-1-hard-ib-aa-sl

Calculate the instantaneous rate of change of f\left(x\right) when x = 2.

13b
4 marks

Calculate the average rate of change of f\left(x\right) between x = 2 and

(i) x = 3

(ii) x = 2.5

(iii) x = 2.25

13c
2 marks

Explain what would happen if you continued to calculate the average rates of change in part (b), moving the second x value closer and closer to 2 each time.

14a
6 marks

A curve has equation y = \frac{1}{6}x^{3} - \frac{3}{8}x^{2} - \frac{3}{2}x + 4.

Find the coordinates of the points on the curve where the gradient is 2. You must show all your working, and give your answers as exact fractions.

14b
3 marks

Find the values of x for which the curve is increasing.

1a
1 mark

The volume of a sphere of radius r is given by the formula V = \frac{4}{3}\pi r^{3}.

Find \frac{\mathrm{d}V}{\mathrm{d}r}.

1b
2 marks

Find the rate of change of V with respect to r when r = 5. Give your answer in terms of pi.

1c
3 marks

Show that \frac{\mathrm{d}V}{\mathrm{d}r} is an increasing function for r > 0.

2a
3 marks

A curve has equation y = f\left(x\right), where f\left(x\right) = \frac{1}{3}x^{3} - 2x^{2} - 4x + \frac{31}{3}.

The points \mathrm{A} and \mathrm{B} are the two points on the curve where the gradient is 1, and the x-coordinate of \mathrm{A} is negative.

Find the coordinates of \mathrm{A} and \mathrm{B}.

2b
5 marks

Find the equation of

(i) the tangent to the curve at \mathrm{A}

(ii) the normal to the curve at \mathrm{B}.

2c
2 marks

The lines in part (b) meet at the point \mathrm{C}.

Find the coordinates of \mathrm{C}.

3a
6 marks

A function f is defined by f\left(x\right) = \frac{1}{5}x^{5} + \frac{2}{3}x^{3} - 3x + 3, for all real numbers x.

(i) Show that the x-coordinates of the points where the gradient of the curve y = f\left(x\right) is zero satisfy the equation \left(x^{2} - 1\right)\left(x^{2} + 3\right) = 0.

(ii) Hence find the coordinates of these points.

3b
3 marks

Find the values of x for which f is

(i) increasing

(ii) decreasing.

3c
3 marks

Sketch the curve y = f\left(x\right), showing the coordinates of any local maximum and local minimum points and of the point where the curve crosses the y-axis.

4
3 marks

Let f\left(x\right) = x^{3} - 3x^{2} + 6x - 7, for x \in \mathbb{R}.

Show that f is increasing for all values of x.

5a
2 marks

An engineer is designing a right cone that is to be produced on a 3D printer. The cone has a base radius of r cm and a height of h cm. The radius may vary, but the height is always 7 cm more than the radius.

Write down an expression for V, the volume of the cone, in terms of r only.

5b
5 marks

The rate of change of V with respect to r is fraction numerator 5 pi over denominator 3 end fraction text  cm end text cubed per cm at a particular value of r.

Find this exact value of r.

6
7 marks

Let f\left(x\right) = ax^{2} + bx + c. The tangents to the graph of f at the points \left(-3, \; d\right) and \left(2, \; -1\right) have gradients 25 and -5 respectively.

Find the values of a, b, c and d.

7a
4 marks

The diagram below shows part of the graph of the function y = f\left(x\right), where f\left(x\right) = 9 - \frac{1}{18}x^{3} - \frac{6}{x}, x > 0.

ib7a-ai-sl-5-1-ib-maths-veryhard

Calculate the average rate of change of f\left(x\right) between x = 3 and

(i) x = 4

(ii) x = 3.5

(iii) x = 3.25.

7b
3 marks

Explain what would happen to the values of the average rates of change in part (a) if you continued to calculate them, moving the second x value closer and closer to 3 each time.

1a
3 marks

A curve has equation y = f\left(x\right), where f\left(x\right) = 2x^{3} + \frac{3}{x} - 4.

The points \mathrm{A} and \mathrm{B} are the two points on the curve where the gradient is 3, and the x-coordinate of \mathrm{A} is negative.

Find the coordinates of \mathrm{A} and \mathrm{B}.

1b
5 marks

Find the equation of

(i) the tangent to the curve at \mathrm{A}

(ii) the normal to the curve at \mathrm{B}.

1c
3 marks

The lines in part (b) meet at the point \mathrm{C}.

Find the coordinates of \mathrm{C}, giving your answers as exact fractions.

2a
6 marks

A function f is defined by f\left(x\right) = \frac{1}{5}x^{5} - \frac{5}{3}x^{3} + 4x - \frac{38}{15}, for all real numbers x.

(i) Show that the gradient of the curve y = f\left(x\right) is zero when x = 1, and find the corresponding y-coordinate.

(ii) Find the x-coordinates of the other points on the curve where the gradient is zero.

2b
4 marks

Find the values of x for which f is

(i) increasing

(ii) decreasing.

2c
3 marks

Given that f\left(1\right) is greater than the value of f at every other point where the gradient is zero, sketch the curve y = f\left(x\right). Show the x-coordinates of any local maximum and local minimum points, and the coordinates of the point where the curve crosses the y-axis.