$\int\left(-9\sqrt{x}\right)dx$

$\lim_{x\to\infty}\left(\frac{-x^2}{3+\sqrt{\left(x^2+9\right)}}\right)$

$^{\cos^2\left(z\right)}$

$\lim_{x\to0}\left(\frac{2x^2+4x-16}{x^4-4x^2}\right)$

$\lim_{x\to2}\left(\frac{2-x}{\frac{1}{2}-\frac{1}{x}}\right)$

$x^2\:-\:x\:-\:7\:=\:0$

$36^2-12b+1$