$900+200+-500$

$y^2-9y=\sin\left(2x\right)$

$45-2\cdot\left(15-3\right)$

$2\log_{12}\left(x-9\right)+\log_{12}4=2$

$4m^4.m$

$\int_{-\frac{1}{2}}^{\frac{1}{2}}\left(cos\left(\pi\cdot x\right)\right)dx$

$\csc2\left(x\right)=\frac{\csc\left(x\right)}{2\cos\left(x\right)}$