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Identify a counterexample to disprove n3 ≤ 3n2, where n is a real number.

User Alwinc
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1 Answer

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n^3\le3n^2\iff n^3-3n^2\le0\iff n^2(n-3)\le0

The quantity on the left hand side will be positive for any
n>3, so suppose consider
n=4.

Now,


4^3=64

but


3(4)^2=48

and
64\\ot\le48
User Andrei Amarfii
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