Question

Qual a integral de ln(x)

Answer 1

$\displaystyle \int \ln x \;dx =x\ln x - \int x d(\ln x)\\ \\ \int \ln x \;dx =x\ln x -\int x \cdot \dfrac{1}{x}\; dx\\ \\ \int \ln x \;dx =x\ln x -\int dx\\ \\ \boxed{\boxed{\int \ln x \;dx =x\ln x - x + C}}$