$\frac{dy}{dx},\left(\sqrt{x}\right)^y=\left(\sqrt{y}\right)^x$

$\frac{2\:.\:x^3y^8}{4\:.\:y^2}$

$16x^4+8x^2+1$

$\lim_{x\to-\infty}\left(\frac{\sqrt{4x^2+1}}{1-x}\right)$

$\left(\frac{1}{5}x+\frac{2}{3}\right)^2$

$x-15-\frac{1}{3}\left(x-15\right)=32$

$\frac{12^{-2}}{2^{-2}}$