$2^{2x+3}=30+2^x$

$\lim_{x\to0}\left(\sqrt{x}\ln\left(x^2\right)\right)$

$\lim_{x\to0}\left(\frac{\sqrt{x^2+y^2+1}-1}{x^2+y^2}\right)$

$2\left(x-1\right)\left(x-3\right)$

$3\left(2x\:-\:4\right)\:=\:4\left(ax\:-\:2\right)$

$6x^4+6x$

$\lim_{x\to d}\left(\frac{x^3-d^3}{x-d}\right)$