$\lim_{x\to-2}\left(\frac{\frac{1}{x\:+\:2}-\:\frac{1}{2}}{x\:}\right)$

$\int\frac{x^2+x+1}{x\left(x^2+4\right)}dx$

$\lim_{h\to0}\left(\frac{\sqrt[3]{5+h}-\sqrt[3]{5}}{h}\right)$

$\log_x\left(4\right)=16$

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

$\int e^{4x^3}x^2dx$

$1x^2-1x^2$