BdMO National Secondary 2015/2
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- Posts:1007
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How many pairs of integers ($m,n$) satisfy the equation $m+n=mn$ ?
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- Posts:1007
- Joined:Sat Dec 09, 2017 1:32 pm
Re: BdMO National Secondary 2015/2
Hint
Answer
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- Posts:1007
- Joined:Sat Dec 09, 2017 1:32 pm
Re: BdMO National Secondary 2015/2
Solution
Re: BdMO National Secondary 2015/2
The solution is ( m,n ) = (2,2)
n and n-1 are co prime unless n-1=1
which makes n=m=2
n and n-1 are co prime unless n-1=1
which makes n=m=2
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- Posts:1007
- Joined:Sat Dec 09, 2017 1:32 pm
Re: BdMO National Secondary 2015/2
(0,0) is also a solution
LHS=0/(0-1)=0/-1=0
RHS=0×0=0