(a)[4]
Show that $\frac{dy}{dx} = 6\cos^5\theta - 5\cos^3\theta$.
(b)[5]
Find the equation of the normal to the curve at the point where it meets the $x$-axis. Give your answer in the form $y = mx + c$, where $m$ and $c$ are exact constants.
Mathematics 9709 · AS & A Level · Differentiation
Show that $\frac{dy}{dx} = 6\cos^5\theta - 5\cos^3\theta$.
Find the equation of the normal to the curve at the point where it meets the $x$-axis. Give your answer in the form $y = mx + c$, where $m$ and $c$ are exact constants.
This 9-mark question has a full step-by-step worked solution and mark scheme. One marking point: “Try to use the chain rule when differentiating $y$, or when simplifying $y$, together with the product rule” …