$y'+y\cdot tan\left(x\right)=cos\left(x\right)$

$\lim_{x\to4}\left(\frac{\sqrt{x}-2}{ax+b}\right)$

$11x-6w-4z\:de\:19z-1w+3x$

$\frac{3x}{2}-\frac{x}{4}$

$\frac{\left(0.8+0\right)+\left(0.8-0\right)}{2}$

$\lim_{x\to3}\:\left(\frac{x^3-2x^2-8x}{x\sqrt{\left(x^2-16\right)}}\right)$

$\int\left(x^4e^{\frac{1}{2}x}\right)dx$