Q. Prove by induction that the sum of the first n positive odd integers is n2.
Base Case of Induction: Let's start with the base case of induction, which is n=1. The first positive odd integer is 1. We need to check if the sum of the first odd integer equals 12. Sum for n=1: 112=1 Since both are equal, the base case holds true.
Assumption for Positive Integer: Now, let's assume that the statement is true for some positive integer k, which is our induction hypothesis.This means we assume the sum of the first k positive odd integers is k2.Sum for n=k: 1+3+5+…+(2k−1)=k2This is our assumption and we will use it to prove the statement for n=k+1.
Proving Statement for n=k+1: Next, we need to show that if the statement is true for n=k, then it must also be true for n=k+1. The sum of the first k+1 positive odd integers would be the sum of the first k odd integers plus the next odd integer, which is 2(k+1)−1. Sum for n=k+1: 1+3+5+…+(2k−1)+[2(k+1)−1] Using our induction hypothesis, we can replace the sum of the first k odd integers with k2. So, Sum for n=k+1: n=k1
Simplifying the Expression: Now, let's simplify the expression for the sum of the first k+1 odd integers.Sum for n=k+1: k2+[2k+2−1]Sum for n=k+1: k2+2k+1Sum for n=k+1: (k+1)2This shows that the sum of the first k+1 positive odd integers is indeed (k+1)2, which is what we needed to prove.
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