$\lim_{u\to z}\left(\frac{u^2-2u+1}{u^2-4}\right)$

$\lim_{x\to\infty}\left(\frac{\ln\left(t\right)}{\sqrt{t}}\right)$

$-2\left(4\right)+3\left(-3\right)^2$

$\lim_{x\to\infty}\left(\frac{15e^x}{11\sqrt{x}}\right)$

$6x^2+3xy^3-3xy^2$

$\frac{x}{3}+5=2$

$\int_3^6\sqrt{x^2+9}dx$