$\frac{\left(-8\right).\left(-5\right)}{\left(-4\right)}$

$\int_0^a\left(x\sqrt{a^2-x^2}\right)dx$

$\int_0^{\frac{\pi}{2}}\left(1-\cos\left(x\right)-\sin\left(x\right)\right)\cdot\left(\sin\left(x\right)-1+\cos\left(x\right)\right)dx$

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

$\left(\left(8t\right)-\left(1\right)\right)^3$

$12-8-\left(7+5-1\right)$

$\int3x^5\sqrt{8x^6+3}dx$