(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

f(x,y)= ln(x+y) -x^2 - y^2

1. Find the partially derivatives

2. Find the stationary points (roots) of the function

2. Relevant equations

3. The attempt at a solution

Quite simple, except i dont know what to do with the ln part, this is my attempt tho

f'x= 1/(x+y) -2x

f'y= 1/(x+y) -2y

Is this right? I am not sure what the derivative of ln (x+ c) is c= constant

2. Roots= where the function crosses the x-line right? So I simply set f'x=0 and solve it to get the root?

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: Stationary points (roots) of partially derivated function

**Physics Forums | Science Articles, Homework Help, Discussion**