$\lim_{x\to-2}\left(7x^2-4x^3-7\right)$

$\int\frac{4x^2-8}{x\left(x^3+2x^2\right)}dx$

$\int_{1-2x}^{1+2x}\left(tsin\left(t\right)\right)dx$

$3+\frac{6}{2}$

$\left(a-8\right)\left(a-15\right)$

$45:5-\left(8-6\right)\cdot\left(-8\right)-\left[3-\left(-9-6\right)\right]\cdot4$

$\lim_{x\to0}\left(\frac{1-x}{\tan\left(x\right)}\right)$