$\left(6x+b\right)\left(6x+3\right)$

$\frac{\left(2sin\left(\frac{8x}{2}\right)cos\left(\frac{6x}{2}\right)\right)}{\left(-2sin\left(\frac{8x}{2}\right)sin\left(\frac{6x}{2}\right)\right)}$

$-2xy\left(3x^6\right)$

$\frac{7x^3-x+2+2}{x+2}$

$x-\frac{12}{\left(x+2\right)\left(x-5\right)}$

$\int\frac{4}{\sqrt{9x^2+4}}dx$

$\int x\left(36+x^2\right)dx$