$\lim_{t\to0}\left(\frac{x^2t-xt^2}{t\left(x^2-t^2\right)}\right)$

$\int\left(\frac{r}{\sqrt{16-9r^4}}\right)dr$

$421\cdot23$

$5\:-\:\left(\:8\:\cdot\:8\:-\:2\:\right)\:$

$\left(x^{\frac{4}{7}}\right),\sqrt[4]{x^7}$

$\left(6a^5b^{-7}\right)\left(6a^{-2}b^5\right)\left(6a^{-8}b^4\right)$

$f\left(x\right)=\frac{1}{4}\left(ln\left(2x+1\right)\right)-ln\left(1-2x\right)$