excuse me for my bad english, but i'm trying hard. 1. function f(x), for x>0 is defined with: f(x)=(x^4)^(x^2) ^ - potency find stationary points of the function f(x) on the interval (0,infinite). what exactly do i do here? do i use logarithm on both sides, and then i get: log(y)=(x^2)*log(x^4) and then i different (differential) both sides, and set y'=0 and i calculate x? is this right so far? now i want to get local min. and max. and i different again, and then what? and i need to find out if these points are globlal min and max. 2. integral from 1 to infinity (((x^2+1)^(1/2))/((x^3)*(x^2-1)^(1/2)))dx and ideas what could i do? what would "u" be? (u^2)=(x^2)+1? please help me asap thank you!