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Answer:
Assume that Sk is valid for n=k and prove that Sn is valid for n= k+ 1
Step-by-step explanation:
This is Principle of Mathematical Induction ---PMI
Step 1: Verify that Sn is valid for n =1
Step 2:Assume that Sk is valid for n=k and prove that Sn is valid for n= k+ 1