Mathematics

Problem

Which of the following is the derivative of

f(x)=\dfrac{\sin x}{x}

for

x\neq 0

? a)

\dfrac{x\cos x+\sin x}{x^{2}}

\dfrac{x\cos x-\sin x}{x^{2}}

\dfrac{x\cos x-\sin x}{x}

\dfrac{\cos x}{x}