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Topic: Building an Equation to find (Maximum Y) ie Highest Point on a curve!
Replies: 14   Last Post: Sep 14, 2013 3:40 PM

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 Thomas Nordhaus Posts: 433 Registered: 12/13/04
Re: Building an Equation to find (Maximum Y) ie Highest Point on
a curve!

Posted: Sep 11, 2013 5:40 PM

Am 11.09.2013 19:46, schrieb mervynmccrabbe@gmail.com:
> On Wednesday, September 11, 2013 4:28:51 PM UTC+1, mervynm...@gmail.com wrote:
>> x^4 + y^4 + A(x^2) - A(y^2) + 2(x^2)(y^2) - Bxy + C = 0
>>

>
> (***) 5x^4 + y^4 + 3Ax^2 - Ay^2 + 6x^2y^2 + C = 0
>

>> then I could manage the rest.
> ------------------------------------------------------------
> Thank You Thomas
> (***) 5x^4 + y^4 + 3Ax^2 - Ay^2 + 6x^2y^2 + C = 0
> Can you handle (***)? This is a quadratic equation in X=x^2 and Y=y^2.
>
> On Reflection No I can not handle an equation with both variables still in it. Any advice?

I made a mistake. According to may proposal you have to multiply by x
and _subtract_ from the original equation. But it leads into a dead end.
Sorry, don't see how that leads to an easy algebraic solution.

--
Thomas Nordhaus