- #1
funzsquare
- 9
- 0
urgent! second derivative test for functions of 2 variables
f(x,y)=x^4 - y^2 - 2x^2 + 2y - 7
classify points (0,1) and (-1,1) as local maximum, local minimum or inclusive
f(x,0)=4x^3 - 0 - 4x + 0 - 0 = 4x^3-4x
f'(x,0)=12x^2-4
f''(x,0)=24x
f(0,y)=0 - 2y - 0 + 2 - 0 = -2y+2
f'(0,y)=-2
f''(0,y)=0
how to find the points as above? as i am stuck.
Homework Statement
f(x,y)=x^4 - y^2 - 2x^2 + 2y - 7
Homework Equations
classify points (0,1) and (-1,1) as local maximum, local minimum or inclusive
The Attempt at a Solution
f(x,0)=4x^3 - 0 - 4x + 0 - 0 = 4x^3-4x
f'(x,0)=12x^2-4
f''(x,0)=24x
f(0,y)=0 - 2y - 0 + 2 - 0 = -2y+2
f'(0,y)=-2
f''(0,y)=0
how to find the points as above? as i am stuck.