$-15x=-285$

$\frac{1}{2}\sqrt{a}-\frac{2}{5}\sqrt{a}+\frac{3}{4}\sqrt{a}-\frac{1}{3}\sqrt{a}$

$6a-3x$

$\frac{d}{dx}\left(y=\left(x^2+4\right)^{10}\left(2x-5\right)^8\right)$

$x^2-8x+16-\left(x^2-12x+36\right)+20$

$3257\cdot109$

$\int\frac{5x^2}{\left(196+x^2\right)^2}\:dx$