$\left(7b^2d-3z^3\right)\left(7b^2d+3z^3\right)$

$\lim_{x\to\infty}\left(\frac{5^x}{8x^2-5^x}\right)$

$14-\left(-750\right)$

$\lim_{x\to0}\left(x+e^{\frac{x}{6}}\right)^{\frac{6}{x}}$

$\lim_{x\to\infty}\left(\frac{x^2+2x+1}{x+1}\right)$

$\int_0^2\left(t\left(t^2\:+\:1\right)^7\:j\:\right)\:dt$

$64x^2-81y^6$