$x^4-19x^2-30x$

$\left(1321\left(-1\right)x^5\right)^{\frac{1}{5}}+\left(16x^2\right)^{\frac{1}{4}}$

$\int\left(x^7\sqrt{x^8-5}\right)dx$

$\frac{d}{dx}\left(\frac{x}{\left(1+x\right)^2}\right)$

$\int x^7cos\left(4x\right)dx$

$2\log x-2\log\left(x-1\right)=0$

$\frac{4x^3-12x^2+9x+0}{2x+1}$