9709 P12 - Jun 2015 - Q11
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The function g is defined by \(g : x \mapsto 2x^2 - 6x + 5\) for \(0 \leq x \leq 4\).
- Express \(g(x)\) in the form \(a(x + b)^2 + c\), where \(a, b\) and \(c\) are constants.
- Find the range of \(g\).
The function h is defined by \(h : x \mapsto 2x^2 - 6x + 5\) for \(k \leq x \leq 4\), where \(k\) is a constant.
- State the smallest value of \(k\) for which \(h\) has an inverse.
- For this value of \(k\), find an expression for \(h^{-1}(x)\).
