$\int_0^{\infty}\left(3tx^2e^{-tx^3}\right)dx$

$-33\cdot\:\left(62-38\right)$

$\lim_{x\to\frac{1}{2}}\frac{x^2}{1-2x}-\frac{1}{1-2x}$

$\int7e^{7x}sin\left(x\right)dx$

$-2a^2b-4a+8+a^2b-12-8a+12+7a^2b$

$\left(3ab\right)^2+\left(-5a\right)\left(-4ab\right)\left(-b\right)$

$y'=2y^2$