$\lim_{x\to0}\left(\frac{7^x-3^x}{2x}\right)$

$3x\left(x-1\right)-2y\left(x-1\right)+z\left(x-1\right)$

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

$36x^2-24x+16$

$-3^2-3-1$

$2\cot\left(y\right)\sin\left(y\right)+\cot\left(y\right)=0$

$\left(y^2+6y^3-8\right)-\left(2y^4-3y^3+6y\right)$