Answer
$f(x)=g(x)+h(x)$
Work Step by Step
$g(x)+h(x)=\frac{1}{2}[f(x)+f(-x)]+\frac{1}{2}[f(x)-f(-x)]=\frac{1}{2}[f(x)+f(-x)+f(x)-f(-x)]=\frac{1}{2}[2f(x)]=f(x)$
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