Finding Max and Min with Lagrange Multipliers: Homework Help

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Homework Statement



find the max and min of f(x,y)=x^2y, constraint x^2+y^2=1

Homework Equations



None.

The Attempt at a Solution



I found that possible points use the procedure of the method of lagrange multiplier, I got (\pm\sqrt{2/3}, \pm\sqrt{1/3} so 4 points total.
But do I have to check the end point on the constraint? like points (-1, 0), (1, 0), (0, 1), (0, -1)?and y this latex thing won't work? help please. lol
 
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You should check the boundaries because for 1) they could have max or min depending contexts and 2) they will give you some sanity towards the answer you have.
 
Change the direction of the slash on your closing tex tag. [\tex] sould be [ /tex] (witout the space obviously)
 
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...
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