$y^{10}d^{10}y^{-4}d^{20}$

$\frac{2x^2}{x^2}$

$\lim_{x\to0}\left(\cos\left(x\right)\left(1+\tan\left(2x\right)^{\frac{4}{x}}\right)\right)$

$4\left(9+15\right)-\left(8-9\right)$

$\int\frac{1-2\cos\left(x\right)^2+\cos\left(x\right)^4}{\cos\left(x\right)^6}dx$

$\int\frac{9x\cos^2\left(7x^2\right)}{\sin\left(7x^2\right)}dx$

$-x+x^2-x^3+x^4-x^5$