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Prove by the principle of mathematical induction:(ab)n = an bn for all n ϵ N |
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Answer» Suppose P (n): (ab)n = an bn Now let us check for n = 1, P (1): (ab)1 = a1 b1 : ab = ab P (n) is true for n = 1. Then, let us check for P (n) is true for n = k, and have to prove that P (k + 1) is true. P (k): (ab)k = ak bk … (i) Now we have to prove, (ab)k + 1 = ak + 1.bk + 1 Therefore, = (ab)k + 1 = (ab)k (ab) = (ak bk) (ab) using equation (1) = (ak + 1) (bk + 1) P (n) is true for n = k + 1 Thus, P (n) is true for all n ∈ N. |
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