$\frac{d}{dx}\:\frac{1}{2\:}\:csc\:\frac{x}{4}$

$\left(x^2y+xy^2\right)\cdot\left(x^2y-xy^2\right)$

$\frac{d}{dx}ye^{3x}=x^2-2y+6$

$j+j+k+j+j+i+h+i+h-k$

$\left(\frac{5}{3}y^2+\frac{6}{5}z^4\right)^2$

$\left(\frac{3}{5m}+\frac{1}{2}\right)^2$

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