$2\:\left(x\:+\:6\right)\:+\:3x\:+\:4$

$\frac{\left(sec\left(x\right)\:+1\right)}{\left(sec\left(x\right)\:-1\right)}\:+\:\frac{\left(cos\left(x\right)\:+1\right)}{\left(cos\left(x\right)\:-1\right)}\:$

$\int20\:sen\:t\:dt$

$\lim_{x\to0}\left(\frac{e^2-sin\left(x\right)-1}{x^4+3x^3+7x^2}\right)$

$2x\:-\:5\:<\:9$

$9v^2\left(2v^2+4\right)$

$\left(\sin\left(b\right)+\cos\left(b\right)\right)^2=1+2\left(\sin\left(b\right)\right)\cdot\cos\left(b\right)$