1. The problem statement, all variables and given/known data Find the critical points for the function g(x, y, z) = x3+xy2+x2+y2+3z2. 2. Relevant equations 3. The attempt at a solution I've come up with the following 3 equations (derivatives set so that they are equal to 0) (1) 3x2+y2+2x=0 (2) 2xy+2y=0 (3) 6z=0 From (3), z=0From (2), 2y(x)+2y(1)=0 x+1=0 x=-1From (1) using what I have obtained from (2), 3(-1)2+y2+2(-1)=0 3-2+y2=0 1=-y2 y2=-1I do not know how I am supposed to isolate y in this case since square roots are supposed to be positive. Do I need to get i involved? If so, how?