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I'm
Nov1-09, 11:05 PM
1. The problem statement, all variables and given/known data

is( X^2 )y + (Y^2)x = 6, then the second derivative at the point (1,3) is ?

2. Relevant equations



3. The attempt at a solution

I don't see how this is possible, when I plug in 1 and 3 it comes out as 9 = 6 which isn't true. Can someone tell me if this is wrong? or if the problem is written badly?

lanedance
Nov1-09, 11:47 PM
fair point, but i get 12

( X^2 )y + (Y^2)x = (1)3 = (3^2)1 = 12
are you maybe missing a factor of 2?

I'm
Nov1-09, 11:58 PM
you're right its 12 but how can I solve the problem?

temaire
Nov2-09, 12:01 AM
you're right its 12 but how can I solve the problem?

Have you tried solving for the second derivative first?

lanedance
Nov2-09, 12:02 AM
well as you point out, (1,3) is not a point on the curve defined by
(x^2)y + (y^2)x = 6, so you can't really

can you write the exact question?

I'm
Nov2-09, 12:04 AM
Thats the equation I was given.

lanedance
Nov2-09, 12:35 AM
it may help if you write the whole question verbatim

but as already said, (1,3) is not a point on the curve defined by (x^2)y + (y^2)x = 6, so the question does not make sense - it is undefined