$\sin\left(x\right)\cdot\cos\left(x\right)+\sin\left(x\right)\cdot\cos\left(x\right)=\frac{\sqrt{2}}{2}$

$\left(4x+15\right)^2$

$x\:2\:+4x+34x\:2\:+12x$

$3x+83x-8$

$\:13\:+\:\left(-\:12\right)\:+\:15+\:\left(-\:16\right)\:+\:18\:+\:\left(-\:19\right)\:+\:\left(-\:21\right)\:+\:20\:$

$\int\left(4xln7x\right)dx$

$\log_a\left(x^n\right)=n\cdot\log_a\left(x\right)$