Mathematics 9709 · AS & A Level · Differentiation

Differentiation — practice question

The curve is given by $\frac{d^2 y}{dx^2} = 6x^2 - \frac{4}{x^3}$. Its stationary point is at $(-1, \frac{9}{2})$.
(a)[1]

Determine the type of stationary point at $(-1, \frac{9}{2})$.

(b)[5]

Find the equation of the curve.

(c)[3]

Show that there are no further stationary points on the curve.

(d)[3]

Point $A$ moves along the curve, and the $y$-coordinate of $A$ is rising at 5 units per second. Determine the rate at which the $x$-coordinate of $A$ is increasing at the point where $x = 1$.

Worked solution & mark scheme

This 12-mark question has a full step-by-step worked solution and mark scheme. One marking point: Substitute $x=-1$ into $\frac{d^2y}{dx^2}$ and conclude that it is a minimum.

  • Full mark scheme, point by point
  • Step-by-step worked solution
  • Write your answer & get it marked instantly by AI