$2x^2-3xy$

$y^4-\frac{2y^2}{3}+\frac{1}{9}$

$\int_{\pi}^{2\pi}\left(-\cos\left(x\right)\right)dx$

$\int\cos\left(ax\right)\cdot\cos\left(nx\right)dx$

$13m-m$

$-14-\left(8+7\right)-\left(4+2-3-\left(-4+5\right)\right)$

$3\cos^2\left(x\right)+\sin^2\left(x\right)+5\sin\left(x\right)=0$