$$$\frac{e_{1}}{t}$$$ 关于$$$t$$$的积分

求$$$\int \frac{e_{1}}{t}\, dt$$$。

对 $$$c=e_{1}$$$ 和 $$$f{\left(t \right)} = \frac{1}{t}$$$ 应用常数倍法则 $$$\int c f{\left(t \right)}\, dt = c \int f{\left(t \right)}\, dt$$$：

$${\color{red}{\int{\frac{e_{1}}{t} d t}}} = {\color{red}{e_{1} \int{\frac{1}{t} d t}}}$$

$$$\frac{1}{t}$$$ 的积分为 $$$\int{\frac{1}{t} d t} = \ln{\left(\left|{t}\right| \right)}$$$:

$$e_{1} {\color{red}{\int{\frac{1}{t} d t}}} = e_{1} {\color{red}{\ln{\left(\left|{t}\right| \right)}}}$$

因此，

$$\int{\frac{e_{1}}{t} d t} = e_{1} \ln{\left(\left|{t}\right| \right)}$$

加上积分常数：

$$\int{\frac{e_{1}}{t} d t} = e_{1} \ln{\left(\left|{t}\right| \right)}+C$$

$$$\int \frac{e_{1}}{t}\, dt = e_{1} \ln\left(\left|{t}\right|\right) + C$$$A