Consider a curve for which $\frac{dy}{dx} = \frac{12}{\sqrt{4x + a}}$, where $a$ is constant. Point $P(2, 14)$ lies on the curve, and the normal at $P$ has equation $3y + x = 5$.
(i)[3]
Show that $a = 8$
(ii)[4]
Find the equation of the curve
Worked solution & mark scheme
This 7-mark question has a full step-by-step worked solution and mark scheme. One marking point: “Normal gradient correctly given as $m=-\frac13$” …