Related rates: a sphere has V = (4/3)πr³. If dr/dt = 2, find dV/dt when r = 3. [4]
23.
Find the second derivative of y = sin 2x. [2]
24.
Explain how to decide whether a stationary point is a max, min or point of inflection using the second derivative. [3]
25.
Integration by substitution: ∫ 2x(x² + 1)³ dx. [3]
26.
Find the average value of y = 3x² on [0, 2]. [3]
27.
A curve is y = 1/x. Find the volume generated when the region from x = 1 to x = 2 is rotated about the x-axis. Leave π in the answer if this is on the spec; otherwise find the area under the curve. [3]
28.
State the chain, product and quotient rules in Leibniz or function notation. [3]
29.
A AQA question gives displacement s = t³ − 6t². Find the velocity and acceleration at t = 1. [3]