Prove the following by the principle of mathematical induction:

Let P(n):


For n= 1is true


P(1): =


Since, P(n) is true for n =1


Let P(n) is true for n= k


P(n): - - - - - - - (1)


We have to show that,



Now,



=


=


=


=


=


=


=


Therefore, P(n) is true for n = k + 1


Hence, P(n) is true for all n N


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