Can we post pictures or else its hard to give geometry problems?

But this not of that category, so no difficulty.

]]>He gave 15 minutes.

Please try....

Let 'a' and 'b' be positive integers such that (ab + 1) divides (a^2 + b^2).

Then show that :

(a^2 + b^2) รท (ab + 1) is a square of an integer.

DON'T ATTEMPT IF YOU HAVE DONE BEFORE OR ELSE IT WOULD PROVE TOO EASY.

I could only figure the half way, my sir helped me out.

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