$x^2\frac{dy}{dx}-2xy=3x^4$

$2\cos^2\left(x\right)=\csc^2\left(x\right)\cdot\cos$

$\left(sin\left(a+b\right)-sin\left(a-b\right)\right)$

$\sqrt{\left(x+y\right)}^2-x^2-6x$

$5-8\cos x=3+5\:\sin^2x$

$\frac{d^2}{dx^2}\left(\sin\left(y\right)+\cos\left(x\right)=1\right)$

$17\cdot150$