[tex]\frac{dy}{dx}[/tex] = - [tex]\frac{9}{8x^{4} }[/tex]
let y = [tex]\frac{3}{(2x)^{3} }[/tex] = [tex]\frac{3}{8}[/tex] [tex]x^{-3}[/tex]
differentiate using the power rule
[tex]\frac{d}{dx}[/tex] ([tex]ax^{n}[/tex] ) = na[tex]x^{n-1}[/tex]
[tex]\frac{dy}{dx}[/tex] = - [tex]\frac{9}{8}[/tex][tex]x^{-4}[/tex] = - [tex]\frac{9}{8x^{4} }[/tex]
