Prove that for all positive integers n,9|(11n−2n)
So the base case would be
9 * k = (11*1 - 2 * 1)
9 * k = 9
k = 1 so yes
The inductive hypothesis would be the fact that (11n−2n) is divisible by 9,
So I thought then I would have to show that (11(n+1)−2(n+1)) is divisible by9
11^(n+1) - 2^(n+1)
11^(n) * 11^1 - 2^n * 2^1
(11-2) * (11^n-2^n)
9*(11^n-2^n)
Is this algebraically correct?
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