$\lim_{x\to\infty}\left(\frac{\sqrt{x^4+5}-x^2}{10\cdot x^2}\right)$

$4\left(5\right)^2-7\left(5\right)-6$

$0=e^{-x^2}$

$\frac{8}{x}=\sqrt{\frac{64}{x^2}}$

$3x^4\cdot6x^6$

$\lim_{x\to0}\left(\frac{\left(\ln\left(\cos\left(x\right)\right)^2\right)}{x^5-2x^4}\right)$

$4\left(-6\right)-3$