$\left(1+x\right)\left(1-x\right)\left(1+x^2\right)-1$

$9y+42y+49$

$-2y+2x-3x+9y-6y-2x+x$

$\int\frac{x^{\frac{3}{2}}}{\left(4-x\right)^{\frac{1}{2}}}dx$

$\left(x+6\right)\left(x-1\right)\left(x-4\right)$

$3x^2y^2+9x^2y^2-18xy^2$

$\frac{\cos\left(x\right)\cdot\tan\left(x\right)}{\frac{1}{cos\left(x\right)}}$