|
|
|
|
|
|
|
|
|
|
|
|
$$$\frac{\pi x \sin{\left(7 \right)}}{20}$$$ 的积分
您的输入
求$$$\int \frac{\pi x \sin{\left(7 \right)}}{20}\, dx$$$。
解答
对 $$$c=\frac{\pi \sin{\left(7 \right)}}{20}$$$ 和 $$$f{\left(x \right)} = x$$$ 应用常数倍法则 $$$\int c f{\left(x \right)}\, dx = c \int f{\left(x \right)}\, dx$$$：
$${\color{red}{\int{\frac{\pi x \sin{\left(7 \right)}}{20} d x}}} = {\color{red}{\left(\frac{\pi \sin{\left(7 \right)} \int{x d x}}{20}\right)}}$$
应用幂法则 $$$\int x^{n}\, dx = \frac{x^{n + 1}}{n + 1}$$$ $$$\left(n \neq -1 \right)$$$，其中 $$$n=1$$$：
$$\frac{\pi \sin{\left(7 \right)} {\color{red}{\int{x d x}}}}{20}=\frac{\pi \sin{\left(7 \right)} {\color{red}{\frac{x^{1 + 1}}{1 + 1}}}}{20}=\frac{\pi \sin{\left(7 \right)} {\color{red}{\left(\frac{x^{2}}{2}\right)}}}{20}$$
因此，
$$\int{\frac{\pi x \sin{\left(7 \right)}}{20} d x} = \frac{\pi x^{2} \sin{\left(7 \right)}}{40}$$
加上积分常数：
$$\int{\frac{\pi x \sin{\left(7 \right)}}{20} d x} = \frac{\pi x^{2} \sin{\left(7 \right)}}{40}+C$$
答案
$$$\int \frac{\pi x \sin{\left(7 \right)}}{20}\, dx = \frac{\pi x^{2} \sin{\left(7 \right)}}{40} + C$$$A