$729x^6+64y^6$

$9x^2-1y^2$

$\int\left(\frac{-4x^3+7x^2+x+4}{x^2\cdot\:\left(x+1\right)\cdot\:\left(x-5\right)}\right)dx$

$-2\left(4\right)+2\left|-3\left(2\right)+\left(-5\right)\left(-5\right)\right|$

$\lim_{x\to1}\left(\frac{ln\left(x\right)-1+x}{x^2-1}\right)$

$\lim_{x\to\infty}\left(\frac{13x}{13x+10}\right)^{8x}$

$\int31^{-x}dx$