Find all functions $f:\mathbb {R}^+\to \mathbb {R}$ such that
1.$\exists a\in \mathbb {R}^+$ such that $f(a)=1$
2.$f(x)f(y)+f\left (\frac {a}{x}\right )f\left (\frac {a}{y}\right )=2f(xy)$
F.E. from Fahim Vai
- Phlembac Adib Hasan
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- Phlembac Adib Hasan
- Posts:1016
- Joined:Tue Nov 22, 2011 7:49 pm
- Location:127.0.0.1
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Re: F.E. from Fahim Vai
Solution:(Somebody check it, please!)