no. of integers

\hspace{-16}$How many Integer $\mathbf{n}$ are there such that $\mathbf{n+20}$ and $\mathbf{n-20}$ are Perfect Squares\\\\

2 Answers

Let n+20=k² and n-20=l²
(k+l)(k-l)=40
So, solutions are n=29 and 101
Ans.2

1708

man111 singh ·2012-01-01 06:36:59

Yes arnab you are Right , Thanks

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