$\frac{tan\left(a\right)}{1+sec\left(a\right)}+\frac{1+sec\left(a\right)}{tan\left(a\right)}=2csc\left(a\right)$

$3mn+m+2mn$

$\frac{x^2\:y}{x^{-1}y}$

$\left(\:10x^8\:-\:9xy^5\:\right)^2$

$x^2-a^3+72^2$

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

$3x^2-4x+1=0$