$\left(\frac{1}{7}w+\frac{2}{5}y\right)^4$

$\frac{e^{-x}-1}{\left(e^{-x}+x\right)^2}$

$\sin^2\left(x\right)\tan^2\left(y\right)=\tan^2\left(x\right)-\sin^2\left(x\right)$

$\left(4ab^3\right)\left(-5a^3b^4\right)$

$2+0\cdot x-x^5$

$\frac{d^2}{dx^2}\left(7x^2-3x^4y^3+y^7\right)$

$\frac{sin\left(x+y\right)}{cosxcosy}=tan\left(x\right)+tan\left(y\right)$