$\left(x-13\right)^2=0$

$\int252x^2\left(7x^3-12\right)^2dx$

$\lim_{x\to1}\left(\frac{\left(1-x+lnx\right)}{1+cos\:5\pi}\right)$

$secy\frac{ctgy+tany}{cscy}$

$.\:\left(\frac{4^2x\left(4^{-1}\right)}{4^{-4}}\right)^3$

$4x^3-y^3y'=0$

$\int\left(\frac{1}{11x-4}\right)dx$