$\frac{50}{\left(cot\:87^{\circ}+cot\:84.2^{\circ}\right)}$

$\lim\:_{x\to\:\infty\:}3x^2+x^3-2x$

$\int\frac{2x^3-1}{-x\left(x^3+1\right)}dx$

$5\cdot2^2-2^3\left(-6+3\right)$

$\lim_{n\to\infty}\left(\frac{2n}{\sqrt{n^2+1}}\right)$

$\int\frac{x^2}{\sqrt{441-x^2}}dx$

$3^3x\:3^5:\:3^2$