$16a+24b\:$

$\frac{\tan\left(u\right)-\cot\left(u\right)}{\sec\left(u\right)}$

$9a^4-6a^2+1$

$\int\left(2x+3\right)\cdot e^xdx$

$\int sin\left(\frac{x}{2}\right)\cdot\cos\left(3x\right)dx$

$\frac{dy}{dt}-y-x=\frac{t}{2}$

$\left(t^2\:+\:1\right)\left(t^4\:-\:t^2\:+\:1\right)$