$-4\left(4-2+5\right)-1-\left|8+\left(-3-1\right)-\left(-7-4\right)\right|$

$\left(\:-\:5\right)\:-\:\left(\:-\:12\right)\:+\:\left(\:-6\right)\:$

$\int e^{9x}\cdot\cos\left(8x\right)dx$

$\lim_{x\to0}\left(\left(\frac{x}{\sqrt{x^2+1}}\right)\right)$

$4x^2+2x-20=0$

$-5\frac{1}{2}+2\frac{3}{4}$

$x^4-x^3+x-1$