$-8=\:-5+3u$

$\lim_{x\to\pi}\:\frac{\left(x-\pi\right)}{tan\left(x\right)}$

$\lim_{x\to\infty}\left(\frac{\left(-2\right)^x\left(x\right)}{4+x}\right)$

$\left(\frac{9^7}{9^3}\right)^2$

$\frac{\left(cos\left(x\right)\right)}{\left(1-sin\left(x\right)\right)}=sec\left(x\right)\left(1-sin\left(-x\right)\right)$

$\lim_{x\to1}\left(\frac{2x^4-6x^3+x^2+3}{x-1}\right)$

$-\left(\frac{20}{10}\right)$