정적분 및 가적분 계산기
정적분과 광의적분을 단계별로 계산하세요
이 계산기는 단계별 풀이를 보여 주면서 상한과 하한이 있는 정적분(진정적분 포함)을 계산하려고 시도합니다.
Solution
Your input: calculate $$$\int_{1}^{e}\left( \ln{\left(x \right)} \right)dx$$$
First, calculate the corresponding indefinite integral: $$$\int{\ln{\left(x \right)} d x}=x \left(\ln{\left(x \right)} - 1\right)$$$ (for steps, see indefinite integral calculator)
According to the Fundamental Theorem of Calculus, $$$\int_a^b F(x) dx=f(b)-f(a)$$$, so just evaluate the integral at the endpoints, and that's the answer.
$$$\left(x \left(\ln{\left(x \right)} - 1\right)\right)|_{\left(x=e\right)}=0$$$
$$$\left(x \left(\ln{\left(x \right)} - 1\right)\right)|_{\left(x=1\right)}=-1$$$
$$$\int_{1}^{e}\left( \ln{\left(x \right)} \right)dx=\left(x \left(\ln{\left(x \right)} - 1\right)\right)|_{\left(x=e\right)}-\left(x \left(\ln{\left(x \right)} - 1\right)\right)|_{\left(x=1\right)}=1$$$
Answer: $$$\int_{1}^{e}\left( \ln{\left(x \right)} \right)dx=1$$$