$-15\:.\:8\:-\:\left(-\:128\:+\:256\right)\::\:\left(-\:7\:+\:3\right)\:+\:\left(-\:135\:+\:128\right)\:.\:3\:$

$26x^2y^6-13x^6y^2+169w^2y^2$

$\frac{\left(1-cos\left(x\right)\right)}{1+cos\:\left(x\right)}=\frac{1}{1-cot\left(x\right)}$

$cosx=-\frac{1}{2}$

$y=2\sin^3\left(\ln\left(5x\right)\right)$

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

$\int\frac{\cos4x}{2+\sin4x}dx$