$-7cos^2x=7sin2x$

$\lim_{w\to\infty}\left(\frac{e^{-6w}}{4+e^{-3w}}\right)$

$5m^2-n^2+4n^2-6m^2+7n^2-2n$

$6x^4-8x^3-2x^2$

$0.05\left(2x\:+\:8\right)\:-\:4x\:+\:2\left(3y\:+\:5\right)\:-\:22$

$\left(2x^2+y^2\right)dx+\left(2xy+3y^2\right)dy=0$

$\frac{5}{3}x+7;\:x=\:3$