$\frac{1-\tan^{2}x}{1+\tan^{2}x}=1-2\sin x$

$\int et\:costdt$

$\int_0^{\infty}\frac{10\sin\left(4\right)}{4}dx$

$\left(m^3n^2-6b\right)\left(m^3n^2-2b\right)$

$10x^2+x-21=0$

$\lim_{x\to infty}\left(\frac{4x}{\sqrt{2x^2+1}}\right)$

$\left(5\cdot\left(3+2\right)\right)+8$