$\left(12x^5\right)+\:\left(3x^4\right)$

$\int x^3\sqrt{1-9x^2}dx$

$\frac{1^1+a^3}{1+na}$

$-7x-2-9y+10x$

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

$36m^2-81=0$

$\frac{\sin\left(x\right)^2}{\cos\left(x\right)^4}-\frac{\sin\left(x\right)}{\cos\left(x\right)}$