$\lim_{x\to0}\frac{\sqrt{x}}{x+1}$

$\lim_{x\to7}\left(\frac{x-3-\sqrt{x^2-13}}{x-7}\right)$

$\left(x^a\right)^2$

$\lim_{x\to0}\left(\frac{\sqrt{a+2x}-\sqrt{a-4x}}{x}\right)$

$x2+7x+9=0$

$\frac{d^4\left(senx+cosx\right)}{d\cdot x^4}$

$\int\frac{2}{\left(4x^2+3\right)^{\frac{3}{2}}}dx$