$x\cdot4^{8\:}\:$

$\left(-4a^2b+5b\right)\left(4a^2b+5b\right)$

$\int_1^{\infty}\left(\frac{2x^2+8x+14}{x\left(2x+9\right)}\right)dx$

$\left(cotx+cscx\right)\cdot\left(tanx-sinx\right)$

$2+\left(-89\right)$

$\int\frac{1-x+2x^2-x^3}{x\left(x^2+1\right)^2}\:dx$

$\frac{d}{dx}y+y^4=x$