Question

\(\dfrac{d}{dx}\big(\sin2x+e^{x}-\cos x\big)=\) ?

• A. \(\cos2x+e^{x}-\sin x\)
• B. \(2\cos2x+e^{x}+\sin x\)
• C. \(2\cos2x+e^{x}-\sin x\)
• D. \(-2\cos2x+e^{x}+\sin x\)

Hint:

Derivative of $-\cos x$ is $+\sin x$; watch the sign.

Answer 1

The Correct Option is B

\(\dfrac{d}{dx}(\sin2x)=2\cos2x\); \(\dfrac{d}{dx}(e^{x})=e^{x}\); \(\dfrac{d}{dx}(-\cos x)=+\sin x\). Sum them to get \(2\cos2x+e^{x}+\sin x\).