Express ${x^2} + 4x - 2$ in the form ${(x + a)^2} + b$ where $a,{\text{ }}b \in \mathbb{Z}$.

If $f(x) = x + 2$ and $(g \circ f)(x) = {x^2} + 4x - 2$ write down $g(x)$.

${(x + 2)^2} - 6$    A1A1

[2 marks]

$(g \circ f)(x) = {(x + 2)^2} - 6$     (M1)

$\Rightarrow g(x) = {x^2} - 6$     A1

[2 marks]

Well done by most candidates.

Well done by most candidates. Those students who lost marks on this question tended to do so in part (b), seemingly through misinterpreting the question.