Florian Mayer
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 Apr 18 awarded Scholar Apr 18 accepted Prove for which $n \in \mathbb{N}$: $9n^3 - 3 ≤ 8^n$ Oct 15 awarded Student Oct 15 comment Prove for which $n \in \mathbb{N}$: $9n^3 - 3 ≤ 8^n$ How does it follow that the inequality is true for n=2 where obviously the statement isn't, but false at n=1 where the statement is? bit.ly/ndBnQX Oct 15 comment Prove for which $n \in \mathbb{N}$: $9n^3 - 3 ≤ 8^n$ Also, that it's false for n = 2 makes me wonder how any proof that does not take that into account can be correct. Oct 15 comment Prove for which $n \in \mathbb{N}$: $9n^3 - 3 ≤ 8^n$ I have tried it out before and found out it is true for n ≥ 3 (or in fact, for n ≠ 2). Oct 15 revised Prove for which $n \in \mathbb{N}$: $9n^3 - 3 ≤ 8^n$ added 2 characters in body Oct 15 revised Prove for which $n \in \mathbb{N}$: $9n^3 - 3 ≤ 8^n$ edited title Oct 15 awarded Supporter Oct 15 comment Prove for which $n \in \mathbb{N}$: $9n^3 - 3 ≤ 8^n$ Aaah excuse me, I truncated two characters when I copied the formula, it's updated now. Should be clear now too. Sorry. Oct 15 revised Prove for which $n \in \mathbb{N}$: $9n^3 - 3 ≤ 8^n$ edited title Oct 15 comment Prove for which $n \in \mathbb{N}$: $9n^3 - 3 ≤ 8^n$ I can assure you I was assigned the problem. Clarified that I only need natural numbers; Also good but not perfect would be a proof that it's true for n ≥ 3. Oct 14 awarded Editor Oct 14 revised Prove for which $n \in \mathbb{N}$: $9n^3 - 3 ≤ 8^n$ edited title Oct 14 asked Prove for which $n \in \mathbb{N}$: $9n^3 - 3 ≤ 8^n$