$\frac{\tan\:\left(a\right)+\cot\:\left(b\right)}{\cot\left(a\right)+\tan\left(b\right)}-\tan\left(a\right)\cdot\cot\left(b\right)$

$\left(\frac{7}{0}\right)\cdot\left(.10\right)\cdot\left(.80\right)^7$

$4^5+4^5+4^5$

$9\sqrt{12}-2\sqrt{75}$

$\int\frac{2x}{\sqrt{36-\left(3x\right)^2}}dx$

$\frac{\cos\left(u\right)\sec\left(u\right)}{\tan\left(u\right)}$

$\lim_{x\to2}\left(x-2\right)^{x-2}$