$\int7x^2cos\left(2x\right)\:dx$

$\int_{-10}^0\frac{-8x}{\sqrt{2x+1}}\:dx$

$\int\frac{20}{x^2\sqrt{x^2+15}}dx$

$\frac{d^2}{dx^2}\left(4e^{4x}cos\left(5x\right)\right)$

$\lim_{x\to1}\left(\frac{\sqrt{x+3}-2}{x^2}\right)$

$\frac{2}{3}xy-xy$

$-\frac{1}{2}x>=\frac{23}{4}$