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Joined: 16 Aug 2018
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Concentration: General Management, Strategy

If a and b are positive integers and ab> 13, IS a≠b?
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18 Aug 2018, 01:43
ab4,ab2,ab+1,ab+3 ab4=23,33,43,... > ab=27,37,47,... or ab+3=26,36,46,... > ab=23,33,43,...
2) multiples of 8: 8*1,8*2,8*3,8*4,8*5,8*6,8*7,... every second of these will be multiples of 16 since the mulitiplier is even (2,4,6,8...) for the rest, the multiplier (1,3,5..) is odd and does not contain 2 as a factor. hence 8 cannot be root square'd
as we know, the last digit of a square is always 1,4,9,6,5. hence ab cannot be a square or a is not equal to b. hope that helps
