Answer
$5+3\sin ^{2}x\cos x+3x^{2} \cos x^3 $
Work Step by Step
$\dfrac {d}{dx}\left( 5x+\sin ^{3}x+\sin x^{3}\right) =\dfrac {d}{dx}\left( 5x\right) +\dfrac {d}{dx}\left( \sin ^{3}x\right) +\dfrac {d}{dx}\left( \sin x^{3}\right) =5+3\sin ^{2}x\cos x+\cos x^3\times 3x^{2}$
