Find the derivative of $639+436-639$

Find the integral

$\int \frac { \operatorname { ln } x } { x } d x$

Find the integral

$\int x\left(x^2-3\right)dx$

Find the integral

$\int\ln\left(\sqrt{x}+\sqrt{1+x}\right)dx$

Find the integral

$\int12x^5dx$

Find the integral

$\int\left(\frac{\cos\left(x\right)}{x}\right)dx$

Find the integral

$\int\left(x^3+2\right)^23x^2dx$

Find the integral

$\int\frac{cos\left(x\right)}{x}dx$