Difference between revisions of "1969 Canadian MO Problems/Problem 1"
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Hence, <math>a_2^nb_1^n-a_1^nb_2^n=a_3^nb_1^n-a_1^nb_3^n=0</math> and our proof is complete. | Hence, <math>a_2^nb_1^n-a_1^nb_2^n=a_3^nb_1^n-a_1^nb_3^n=0</math> and our proof is complete. | ||
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Revision as of 22:39, 17 November 2007
Problem
Show that if and
are not all zero, then
for every positive integer
Solution
Instead of proving the two expressions equal, we prove that their difference equals zero.
Subtracting the LHS from the RHS,
Finding a common denominator, the numerator becomes
(The denominator is irrelevant since it never equals zero)
From
Similarly,
from
Hence, and our proof is complete.
1969 Canadian MO (Problems) | ||
Preceded by First question |
1 • 2 • 3 • 4 • 5 • 6 • 7 • 8 • | Followed by Problem 2 |