If 2x+2y=u and 2xy=v Find x as a function of u,v y as a function of u,v
Many ways to do this one.
Square the top equation: \[ (2x+2y)^2=u^2\implies 4x^2+4xy+4y^2=u^2 \]Double the bottom one:\[ 2(2xy) = 2v\implies 4xy = 2v \]Subtract bottom from top: \[ 4x^2+4y^2=u^2-2v \]Divide by \(4\):\[ x^2+y^2=\frac{u^2-2v}{4} \]This is just a circle.
Hmm, made a small error.
no x the required is x alone and y alone
Square the top equation: \[ (2x+2y)^2=u^2\implies 4x^2+8xy+4y^2=u^2 \]Quadruple the bottom one:\[ 4(2xy) = 4v\implies 8xy = 4v \]Subtract bottom from top: \[ 4x^2+4y^2=u^2-4v \]Divide by \(4\):\[ x^2+y^2=\frac{u^2-4v}{4} \]This is just a circle.
How do you know that it is even possible?
i do not know
It's not possible to make \(x\) and \(y\) functions of \(v\) and \(u\).
Because the relationship isn't that of a function.
For something as simple as \(y=x^2\), we can make \(y\) a function of \(x\) but \(x\) is not a function of \(y\) because \(y=1\) has \(x=-1\) and \(x=1\) as solutions.
thank you very much
hmm its just a circl lol can u solve it -.-
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