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Bunuel
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­Here's what I did:

I took a square of (a + b)/(a - b) and got
a^2+ b^2+2ab/ a^2+b^2-2ab

Then, I substituted the value of a^2+b^2 which resulted in,
4ab+2ab/ 4ab-2ab = 6ab/2ab = 3

Can anyone please tell me where i am making the mistake?
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vanshikaamittal
­Here's what I did:

I took a square of (a + b)/(a - b) and got
a^2+ b^2+2ab/ a^2+b^2-2ab

Then, I substituted the value of a^2+b^2 which resulted in,
4ab+2ab/ 4ab-2ab = 6ab/2ab = 3

Can anyone please tell me where i am making the mistake?
­You always square on both the LHS and RHS

Let \(\frac{(a+b)}{(a-b)}\) = X

Squaring both the sides,

\(\frac{(a+b)^2}{(a-b)^2}\) = \(X­^2\)­

\(\frac{(a^2+b^2+2ab)}{(a^2+b^2-2ab)}\) = \(X­^2\)­

Substituing the the value of \(a^2+b^2\) = 4ab

\(\frac{4ab+2ab}{ 4ab-2ab}\) = \(X­^2\)­

\(\frac{6ab}{2ab}\) = \(X­^2\)­

3 = \(X­^2\)­

X = \(\sqrt{3}­\)­
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