问题
通过凑微分,如何计算 [$\textcolor{Orange}{\int f(\sin x) \cos x \mathrm{d} x}$] ?选项
[A]. $\int$ $f(\sin x) \cos x$ $\mathrm{d} x$ $=$ $\int$ $f(\sin x)$ $\mathrm{d} (\sin x)$[B]. $\int$ $f(\sin x) \cos x$ $\mathrm{d} x$ $=$ $- \int$ $f(\sin x)$ $\mathrm{d} (\cos x)$
[C]. $\int$ $f(\sin x) \cos x$ $\mathrm{d} x$ $=$ $\int$ $f(\sin x)$ $\mathrm{d} x$
[D]. $\int$ $f(\sin x) \cos x$ $\mathrm{d} x$ $=$ $- \int$ $f(\sin x)$ $\mathrm{d} (\sin x)$
$$\int \textcolor{Red}{f(\sin x)} \textcolor{Green}{\times} \textcolor{Red}{\cos x} \mathrm{d} \textcolor{Yellow}{x} =$$ $$\int \textcolor{Red}{f(\sin x)} \mathrm{d} (\textcolor{Yellow}{\sin x}).$$