$\left[-21+16-\left(-15+3\right)\right]$

$\int\left(x^2\left(\sqrt{9-x^2}\right)\right)dx$

$5.12\cdot10^7$

$\int\left(\sin\left(x+a\right)\right)dx$

$\sqrt[4]{5}x^4+7x^2$

$\frac{dy}{dx}=\frac{\left(2x+5\right)}{\left(y-1\right)}$

$\lim_{x\to\infty}\left(\sqrt{3x-1}-\sqrt{x^2-2x}\right)$