$\left(6s+3\right)\left(6s-3\right)$

$\int sec\:3x\left(sec\:3x+tan\:3x\right)dx$

$\int\frac{1}{x^2\left(x-3\right)+\left(x-3\right)}dx$

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

$\int\left(\frac{x^2+3}{x^3-5x^2+6x}\right)dx$

$-3x^2-7-3x^2+2y^2-8x^2+9xy$

$\sqrt{\frac{1}{4}a^4b}\:\sqrt{\frac{1}{16}a^3b^4}$