Mathematics 9709 · AS & A Level · Differentiation

Differentiation — practice question

The line has equation $y = mx + c$, with $m$ and $c$ as constants, and the curve is defined by $xy = 16$.

(a)[3]

Since the line is tangent to the curve, express $m$ in terms of $c$.

(b)[3]

Given instead that $m = -4$, find the set of values of $c$ for which the line meets the curve at two distinct points.

Worked solution & mark scheme

This 6-mark question has a full step-by-step worked solution and mark scheme. One marking point: “Set up $x(mx+c)=16 \Rightarrow mx^2+cx-16=0$” …