Induction proof of an inequality

AI Thread Summary
The discussion focuses on proving the inequality n! ≤ n^n for all integers n ≥ 1 using mathematical induction. The base case is established with 1! ≤ 1^1, confirming the statement holds for n=1. The inductive hypothesis assumes k! ≤ k^k is true, leading to the need to prove (k+1)! ≤ (k+1)^(k+1). Participants suggest rewriting (k+1)! in terms of k and k^k to facilitate the proof, indicating that the right-hand side of the inequality needs correction. The conversation emphasizes the importance of correctly manipulating the terms to complete the induction step.
nastygoalie89
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Homework Statement



for all integers n>=1, n! <= n^n

Homework Equations





The Attempt at a Solution



Base case: (1)! <= (1)^(1) 1=1 check
Inductive hypothesis: suppose k!<=k^k
P(k+1): (k+1)! <= (k+1)^(k+1)

From here on out I get very confused. Any help would be appreciated!
 
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Write (k+1)! \le (k+1)^{k+1} in terms of k and k^k.
 
so it would be k!(k+1) <= (k+1)^k + (k+1) ?
 
The right hand side is incorrect, but you're on the right track.
 
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