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Given the composition $\displaystyle {h}{\left({x}\right)}={f{{\left({g{{\left({x}\right)}}}\right)}}}$ ,

if $\displaystyle {h}{\left({x}\right)}={\frac{{{5}}}{{{x}+{7}}}}\$ and $\displaystyle \ {g{{\left({x}\right)}}}={x}+{7}\$ , find the function $\displaystyle {f{{\left({x}\right)}}}$ .

$\displaystyle {f{{\left({x}\right)}}}=\frac{{5}}{{x}}$
$\displaystyle {f{{\left({x}\right)}}}=\frac{{{x}+{7}}}{{5}}$
$\displaystyle {f{{\left({x}\right)}}}=\frac{{{x}+{7}}}{{x}}$

$\displaystyle {f{{\left({x}\right)}}}=\frac{{5}}{{x}}+{7}$
$\displaystyle {f{{\left({x}\right)}}}=\frac{{x}}{{5}}$

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