$\int2x\left(8x^2-1\right)^5dx$

$\left(1+\sec\left(x\right)\right)\cos\left(x\right)$

$\int5x\cos\left(4x\right)dx$

$\frac{\sqrt{x+y}}{\sqrt{x-y}-\sqrt{x+y}}$

$\frac{x}{1-x}\ge2$

$\frac{d}{dx}\left(ln\left(\frac{\left(4x+1\right)^2}{\sqrt{\left(x^2+1\right)}}\right)\right)$

$-15+5\left(-2\right)$