$\int9\cdot x\cdot\sec^2\left(3\cdot x\right)dx$

$\left(2ax-1\right)^2$

$\frac{\left(x^2+2x-8\right)}{\left(x+4\right)}$

$9\left(x^2\right)^2-\left(y\right)^2$

$36a^6+64b^2$

$-1-2-\left(3-4-5-6\right)-7-8-9$

$\int_0^{\pi}\left(\frac{\left(\arctan\left(x\right)\right)^2}{1+x^2}\right)dx$