$x^{-3}\cdot x^{b\:}$

$\left(2a\right)+\left(-6b^2\right)+\left(-3a^2\right)+\left(-4b^2\right)+\left(7a\right)+\left(9a^2\right)$

$\frac{\sin\:\left(x-1\right)}{\sin\:\left(x+1\right)}\:=\:\frac{-\cos\:^2\:\left(x\right)}{\left(\sin\:\left(x+1\right)\right)^2}$

$\int xk^{5x^2}dx$

$\int\frac{e^x}{\left(e^x-5\right)\left(e^x+6\right)}dx$

$\frac{1+cosx}{sin\left(x\right)}=\frac{1}{1-cosx}$

$x^2\:+\:x\:1$