Question

cot ( tan^-1 (7x)) find dy/dx

Answer 1

$cot( {tan}^{ - 1} 7x)$
$= cot( {cot}^{ - 1} \frac{1}{7x} )$
$= \frac{1}{7x}$

$\frac{dy}{dx} = \frac{ - 1}{ 7 {x}^{2} }$