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Feb 6th, 2003, 05:18 PM
#1
Thread Starter
Fanatic Member
sum of cubes
we have m^3+n^3+99mn=33^3
find the number of pairs of integers (m,n) for which mn>=0
well, i see that LHS is the expansion of:
(m+n)^3=m^3+3(m+n)mn+n^3
so m+n=33 or m=0 and n=0
we have a total of 34 solutions ie (0,33),(1,32),...,(33,0)
but its a multiple choice question with solutions A)2 B) 3 C)33 D)35 E)99
its driving me crazy that my answer is between 33 and 35!! what am i missing?
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Did you know that...
The probability that a random rational number has an even denominator is 1/3 (Salamin and Gosper 1972)? This result is independently verified by me (2002)!
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