$\left(x^{5}-2x+b\right):\left(x^{2}-4\right)$

$x^2-10x-15$

$4-\left(-7+4-5\right)+\left(-5+1\right)$

$0.18+0.43+0.09+0.18+0.12+0.06$

$\frac{\cot\left(-t\right)+\tan\left(-t\right)}{\cot\left(t\right)}=-\sec^2\left(t\right)$

$\lim_{x\to1}\frac{\sin\left(x\right)}{5x+3\sin\left(x\right)\:}$

$45-\left(-45\right)-\left(-45\right)-\left(-45\right)$