Saturday, 21 November 2015

proof verification - Prove by mathematical induction 4n>n+1

Prove the following by mathematical induction:



4n>n+1, for all integers n1




Step 1:
n=1:



LHS =4(1)=4



RHS =(1)+1=2



LHS > RHS. ∴ P(1) is true.



Step 2:

Assume P(k) is true for some k1



P(k): 4k>k+1



Step 3: We must show P(k+1) is true.



n=k+1: 4k+1>(k+1)+1



RHS = (k+1)+1<4k+1<4k+4k=24k<44k=4k+1 = LHS




Hence, P(k+1) is true. Therefore, By Math. Induction P(n) is true for all n1



Can anyone check if my method is correct or there is a better way to do it. Thank you.

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