Not sure how to solve this system of equations (easy)

bmed90
Messages
99
Reaction score
0

Homework Statement



Im trying to find local min and max values. So I have fx and fy. I need to find critical points by setting them equal to 0


4x^3-4y=0 and 4y^3-4x=0

Homework Equations




4x^3-4y=0 and 4y^3-4x=0

are fx and fy respectively

The Attempt at a Solution



I just need to know how you would solve this set of 2 equations to get the points (0,0),(1,1) AND (-1,-1)
 
Physics news on Phys.org
Solve for one variable in one of the equations, and substute for that variable in the other equation.
 
Yes I tried that, being that is the obvious way to do it. I just couldn't do the algebra. Thanks
 
Nevermind, I got it =D
 

Thread 'Finding the nth roots of a complex number'

There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
View full post »

Similar threads

Obtain a nonzero solution of ##y''-4y'+x^2(y'-4y)=0## by inspection
Replies
7
Views
1K
How do I solve systems of equations to find local max, min, and saddle points?
Replies
2
Views
2K
Another max value on surface (no boundaries)
Replies
8
Views
2K
Linearization of f(x,y) = sqrt(29 - 4x^2 - 4y^2) at (2,1)
Replies
4
Views
1K
Why can't a critical point of a system of DEs be complex?
Replies
27
Views
2K
Can't get Lagrange multiplier to work in a single exercise
Replies
16
Views
3K
Absolute max and min of multivariable function
Replies
4
Views
2K
A differential equation with undetermined coefficients
Replies
5
Views
2K
Solve the following differential equation (by regrouping terms)
Replies
8
Views
3K
A Wronskian- variation of Params Problem
Replies
1
Views
1K

Hot Threads

Recent Insights

Back
Top