Mathematics 9709 · AS & A Level · Differentiation

Differentiation — practice question

Consider the function $f$, given by $f: x \mapsto x^3 - x^2 - 8x + 5$ for $x < a$. It is stated that $f$ increases.

(main)[4]

Determine the greatest possible value of the constant $a$.

Worked solution & mark scheme

This 4-mark question has a full step-by-step worked solution and mark scheme. One marking point: “Differentiate to obtain $f'(x)=3x^2-2x-8$” …