Prove x2+y2+z2+w2=36 for Real Numbers x, y, z, w

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To prove that x² + y² + z² + w² = 36 given the equation (x²/(n²-1)) + (y²/(n²-32)) + (z²/(n²-52)) + (w²/(n²-72)) = 1 for n = 2, 4, 6, and 8, start by substituting these values of n into the equation. This will yield four separate equations involving the variables x, y, z, and w. Solving these equations will provide the necessary relationships between the variables. The approach is straightforward and involves algebraic manipulation to derive the required result. The solution hinges on the consistency of the equations generated from the substitutions.
jeedoubts
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Homework Statement


if the real numbers x,y,z,w satisfy (x2/(n2-1))+(y2/(n2-32))+(z2/(n2-52))+(w2/(n2-72)) for n=2,4,6,8 then prove
x2+y2+z2+w2=36

Homework Equations


The Attempt at a Solution


unable to think of anything?:confused:
 
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Unless I'm missing something, the problem you posted isn't consistent - what do your numbers x, y, z, w satisfy?
 
radou said:
Unless I'm missing something, the problem you posted isn't consistent - what do your numbers x, y, z, w satisfy?


sorry the exact equation is as follows
[(x2/(n2-1))+(y2/(n2-32))+(z2/(n2-52))+(w2/(n2-72))]=1
 
please help:confused::confused:
 
Edit: Add "= 1" to make an equation below.
jeedoubts said:

Homework Statement


if the real numbers x,y,z,w satisfy (x2/(n2-1))+(y2/(n2-32))+(z2/(n2-52))+(w2/(n2-72)) = 1 for n=2,4,6,8 then prove
x2+y2+z2+w2=36




Homework Equations





The Attempt at a Solution


unable to think of anything?:confused:
You're unable to think of anything? The most obvious starting point is substituting n = 2, n = 4, n = 6, and n = 8, and seeing what you get.
 
Mark44 said:
Edit: Add "= 1" to make an equation below.
You're unable to think of anything? The most obvious starting point is substituting n = 2, n = 4, n = 6, and n = 8, and seeing what you get.
That will give you four different equations in four unknowns -- in other words, exactly what is needed to solve the problem.
 
I tried to combine those 2 formulas but it didn't work. I tried using another case where there are 2 red balls and 2 blue balls only so when combining the formula I got ##\frac{(4-1)!}{2!2!}=\frac{3}{2}## which does not make sense. Is there any formula to calculate cyclic permutation of identical objects or I have to do it by listing all the possibilities? Thanks
Since ##px^9+q## is the factor, then ##x^9=\frac{-q}{p}## will be one of the roots. Let ##f(x)=27x^{18}+bx^9+70##, then: $$27\left(\frac{-q}{p}\right)^2+b\left(\frac{-q}{p}\right)+70=0$$ $$b=27 \frac{q}{p}+70 \frac{p}{q}$$ $$b=\frac{27q^2+70p^2}{pq}$$ From this expression, it looks like there is no greatest value of ##b## because increasing the value of ##p## and ##q## will also increase the value of ##b##. How to find the greatest value of ##b##? Thanks
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