Mathematics 0580 · IGCSE · Functions

Functions — practice question

The functions are $f(x)=2x-1$, $g(x)=x^2+x$, and $h(x)=\dfrac{2}{x},\; x\neq 0$.

(a)[2]

Calculate $f(3)$.

(b)[3]

Calculate $gf(x)$, giving your answer in its simplest form.

(c)[2]

Calculate $f^{-1}(x)$.

(d)[4]

Calculate $h(x) + h(x+2)$, giving your answer as a single fraction.

Worked solution & mark scheme

This 11-mark question has a full step-by-step worked solution and mark scheme. One marking point: “The substitution gives $f(3)=2(3-1)+1$.” …