(i)[5]
Show that the derivative is $\frac{dy}{dx} = \frac{2}{3}\cot 2t - 1$.
(ii)[3]
Find the values of $t$ at $A$ and $C$, with each answer correct to 3 decimal places.
(iii)[3]
Find the gradient of the curve at $B$.
Mathematics 9709 · AS & A Level · Differentiation
Differentiation — practice question
For a curve, the parametric equations are $x = 6\sin^2 t$, $y = 2\sin 2t + 3\cos 2t$, for $0 \leq t < \pi$. The curve meets the $x$-axis at $B$ and $D$, and the stationary points are $A$ and $C$, as the diagram shows.
Worked solution & mark scheme
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