Question Bank

Official NZQA past exam questions • AS91578 Differentiation

With video explanations by infinityplusone

15 questions
Achievement
Differentiate y=e3xsin2xy = e^{3x}\sin 2x.

*You do not need to simplify your answer.*
Achievement
The graph below shows the function y=f(x)y = f(x).
Loading diagram...
For the function above:

(i) Find the value(s) of xx that meet the following conditions:

(1) f(x)=0f'(x) = 0:

(2) f(x)f(x) is concave upwards:

(ii) What is the value of limx7f(x)\lim_{x \to 7} f(x):

State clearly if the value does not exist.
A curve has the equation y=(2x+3)ex2y = (2x + 3)e^{x^2}.

Find the xx-coordinate(s) of any stationary point(s) on the curve.

*You must use calculus and show any derivatives that you need to find when solving this problem.*
Excellence
A curve is defined parametrically by the equations x=t2+3tx = t^2 + 3t and y=t2ln(2t3)y = t^2 \ln(2t - 3), for t>32t > \dfrac{3}{2}.

Find the gradient of the tangent to the curve at the point (10,0)(10,0).

*You must use calculus and show any derivatives that you need to find when solving this problem.*
Excellence
A cone has a height of 3 m and a radius of 1.5 m.

A cylinder is inscribed in the cone, as shown in the diagram below.
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The base of the cylinder has the same centre as the base of the cone.

Prove that the maximum volume of the cylinder is π\pi m3^3.

*You must use calculus and show any derivatives that you need to find when solving this problem.*
Achievement
Differentiate f(x)=(1x2)5f(x) = (1 - x^2)^5.

*You do not need to simplify your answer.*
Achievement
A curve has the equation y=x2x+1y = \dfrac{x^2}{x+1}.

Find the xx-coordinate(s) of any stationary point(s) on the curve.

*You must use calculus and show any derivatives that you need to find when solving this problem.*
A curve has the equation y=(x2+3x+2)cos3xy = (x^2 + 3x + 2)\cos 3x.

Find the equation of the normal to the curve at the point where the curve crosses the yy-axis.

*You must use calculus and show any derivatives that you need to find when solving this problem.*
The volume of a spherical balloon is increasing at a constant rate of 60 cm360\ \mathrm{cm}^3 per second.

Find the rate of increase of the radius when the radius is 15 cm15\ \mathrm{cm}.

*You must use calculus and show any derivatives that you need to find when solving this problem.*
Excellence
The graph below shows the curve y=2x4y = \sqrt{2x - 4}, and the tangent to the curve at point P.
The tangent passes through the point (2,1)(-2, 1).
Loading diagram...
Find the coordinates of point P.

*You must use calculus and show any derivatives that you need to find when solving this problem.*
Achievement
Differentiate y=cotxx2+1y = \dfrac{\cot x}{x^2 + 1}.

You do not need to simplify your answer.
Achievement
The graph of the function y=4xx+2y = 4\sqrt{x} - x + 2, where x>0x > 0, has a stationary point at point Q.

Find the coordinates of point Q.

*You must use calculus and show any derivatives that you need to find when solving this problem.*