$3.6502815398728847^2-2\left(3.1622776601683795-4\right)$

$\frac{3+x^3-5x}{x^2+x}$

$\lim_{x\to0}\left(\frac{6x+6sinx}{5x+5cosx}\right)$

$\int\frac{31x-30}{x^2-3x}dx$

$\lim\:_{x\to\:\infty\:}\left(1+\sqrt{x+4}-\sqrt{x}\right)^{\sqrt{x}}$

$\sin\left(x\right)-\cos^2\left(x\right)=\sin^2\left(x\right)$

$\left(\frac{3}{4}x-\frac{2}{3}\right)\left(\frac{3}{4}x+\frac{2}{3}\right)$