$9x^2+18x$

$5+\left(6-\left(8+5-6\right)\right)-\left(7-4+3\right)-\left(2-\left(4-5\right)\right)$

$96+35+\left\{128\right\}-\left\{26\right\}+3$

$\left(a^{-5}b^{-2}\right)\left(3a^1b^7\right)^{-3}\left(a^{-5}\right)^{-4}$

$t\left(\frac{dy}{dt}\right)+6y=4t$

$u=1+\frac{9}{4}x$

$\lim_{x\to0}\ln\left(1+3x^5\right)$