$$$\frac{8 \left(x - 1\right)}{x^{2}}$$$ 的积分
您的输入
求$$$\int \frac{8 \left(x - 1\right)}{x^{2}}\, dx$$$。
解答
输入已重写为:$$$\int{\frac{8 \left(x - 1\right)}{x^{2}} d x}=\int{\frac{8 x - 8}{x^{2}} d x}$$$。
Expand the expression:
$${\color{red}{\int{\frac{8 x - 8}{x^{2}} d x}}} = {\color{red}{\int{\left(\frac{8}{x} - \frac{8}{x^{2}}\right)d x}}}$$
逐项积分:
$${\color{red}{\int{\left(\frac{8}{x} - \frac{8}{x^{2}}\right)d x}}} = {\color{red}{\left(- \int{\frac{8}{x^{2}} d x} + \int{\frac{8}{x} d x}\right)}}$$
对 $$$c=8$$$ 和 $$$f{\left(x \right)} = \frac{1}{x^{2}}$$$ 应用常数倍法则 $$$\int c f{\left(x \right)}\, dx = c \int f{\left(x \right)}\, dx$$$:
$$\int{\frac{8}{x} d x} - {\color{red}{\int{\frac{8}{x^{2}} d x}}} = \int{\frac{8}{x} d x} - {\color{red}{\left(8 \int{\frac{1}{x^{2}} d x}\right)}}$$
应用幂法则 $$$\int x^{n}\, dx = \frac{x^{n + 1}}{n + 1}$$$ $$$\left(n \neq -1 \right)$$$,其中 $$$n=-2$$$:
$$\int{\frac{8}{x} d x} - 8 {\color{red}{\int{\frac{1}{x^{2}} d x}}}=\int{\frac{8}{x} d x} - 8 {\color{red}{\int{x^{-2} d x}}}=\int{\frac{8}{x} d x} - 8 {\color{red}{\frac{x^{-2 + 1}}{-2 + 1}}}=\int{\frac{8}{x} d x} - 8 {\color{red}{\left(- x^{-1}\right)}}=\int{\frac{8}{x} d x} - 8 {\color{red}{\left(- \frac{1}{x}\right)}}$$
对 $$$c=8$$$ 和 $$$f{\left(x \right)} = \frac{1}{x}$$$ 应用常数倍法则 $$$\int c f{\left(x \right)}\, dx = c \int f{\left(x \right)}\, dx$$$:
$${\color{red}{\int{\frac{8}{x} d x}}} + \frac{8}{x} = {\color{red}{\left(8 \int{\frac{1}{x} d x}\right)}} + \frac{8}{x}$$
$$$\frac{1}{x}$$$ 的积分为 $$$\int{\frac{1}{x} d x} = \ln{\left(\left|{x}\right| \right)}$$$:
$$8 {\color{red}{\int{\frac{1}{x} d x}}} + \frac{8}{x} = 8 {\color{red}{\ln{\left(\left|{x}\right| \right)}}} + \frac{8}{x}$$
因此,
$$\int{\frac{8 x - 8}{x^{2}} d x} = 8 \ln{\left(\left|{x}\right| \right)} + \frac{8}{x}$$
加上积分常数:
$$\int{\frac{8 x - 8}{x^{2}} d x} = 8 \ln{\left(\left|{x}\right| \right)} + \frac{8}{x}+C$$
答案
$$$\int \frac{8 \left(x - 1\right)}{x^{2}}\, dx = \left(8 \ln\left(\left|{x}\right|\right) + \frac{8}{x}\right) + C$$$A