$x^2+20x+64$

$\int x^2e^{\frac{2x}{3}}dx$

$4a^2-81b^4$

$\sec\left(x\right)^2+\csc\left(x\right)^2=\frac{1}{\sin\left(\frac{11}{61}\right)^2\cdot\cos\left(x\right)^2}$

$\left(8b+4d\right)\left(7b-6d\right)$

$y'+\cot\left(x\right)y=\frac{1}{\cos\:^2\left(x\right)\sin\left(x\right)}$

$\lim_{x\to\infty}\left(e^x+x\right)^{\frac{3}{2}}$