$-6x+4\left(-x-3\right)$

$\frac{\sin^2\left(x\right)+1}{\cos^2\left(x\right)}+1$

$\left(\frac{x^n}{7^n}+n^n\cdot x^n\right)$

$\left(x^3-3x^2+6x+2\right)\left(6x^2+x+1\right)$

$-4x^2-3+4+3-5^2+3y^2-5y^2$

$\int\left(\frac{\left(ln\left(x^6\right)\right)}{x}\right)dx$

$\frac{-y-y^5+2}{y+1}$