#$9f(x)=10x^2+2x-4$ with domain $(0,).$

$a{f}^{\text{'}}(x),$ and use this $to$ explain why $f$

$is$ one$-do-$one $on$ the given domain.

$b\frac{d{f}^{-1}}{dx}{|}_x=4$

$c{f}^{-1}(f(6))$