# find the value of any relative extrema.

• September 24th 2008, 03:46 PM
plstevens
find the value of any relative extrema.
f(x)=(lnx)^2, x>0

On this particular problem i don't even know how to start so if you would assist me in starting this problem that would be awesome. just help me start and i'm sure i could probably figure out the rest
• September 24th 2008, 04:19 PM
skeeter
start by finding f'(x) and looking for critical vales ...

$f'(x) = \frac{2\ln{x}}{x}$

$2\ln{x} = 0$

$x = 1$

for $0 < x < 1$ , $f'(x) < 0$ ... f(x) is decreasing

for $x > 1$, $f'(x) > 0$ ... f(x) is increasing

so ... what sort of extrema at x = 1?