$2\sin\left(x\right)-4\cos\left(2x\right)=-1$

$\cot^2\left(69\right)$

$\frac{d}{dx}27t^2$

$\int_{\sqrt{3}}^3\left(\frac{12}{9+x^2}\right)dx$

$\left(-7\right)-\left(+2\right)+\left(+8\right)-\left(-4\right)$

$\frac{2\left(12x^2-9x\right)}{3x}$

$\lim_{x\to0}\left(x+cosx\right)^{\frac{1}{2}}$