$\lim_{x\to0}\left(\frac{5^{cosx}-5}{2x}\right)$

$\left(\sqrt{81}\right)-\left(-\sqrt{25}\right)$

$\frac{63}{9x}$

$\frac{\left(2sin\left(x-y\right)\right)}{cos\left(x+y\right)+cos\left(x-y\right)}$

$y^3\sin\left(x\right)+yx^3$

$\frac{dy}{dx}=\frac{2x\:y^3}{\left(1+x^2\right)^{0.5}}\:\:$

$\int\frac{5x^2-4x+6}{\left(x^2+9\right)^3}dx$