Câu hỏi: Nguyên hàm $\int{\left( \sin 2x+\cos x \right)dx}$ là: A. $\dfrac{1}{2}\cos 2x+\sin x+C$. B. $-\cos 2x+\sin x+C$. C. $-\dfrac{1}{2}\cos 2x+\sin x+C$. D. $-\cos 2x-\sin x+C$.
Ta có:
$\int{\left( \sin 2x+\cos x \right)dx}=-\dfrac{1}{2}\cos 2x+\sin x+C$.