$\left(xy+xz+yz\right)\left(x+y+z\right)-xyz$

$-\:2x\:+\:7y\:-\:5x\:+\:x$

$x+y=4\:$

$7x^2+xy$

$p\left(3x\right)+p\left(12\right)=xp+53$

$\lim_{x\to0}\:x^{\frac{1}{8}}ln\left(x\right)$

$\frac{d}{dx}\left(5x^{\frac{7}{2}}-2x^{\frac{3}{2}}+4x^{\frac{-3}{2}}-8x^{-\frac{5}{2}}\right)$