Matematické Fórum

stuart clark · 05. 06. 2012 06:04

Calculate value of $x$ in $x^3-\lfloor x \rfloor = 3$

vanok · 05. 06. 2012 10:34 — Editoval vanok (05. 06. 2012 10:41)

Hi ↑ stuart clark:,
First an observation: $\lfloor x \rfloor$ is an integer, so $x^3$ must be also un integer, and so $x$ must bu an cube root of un integer.
The study of the fonction $f:x \mapsto x^3-\lfloor x \rfloor$ (an increasing function for $x>1$ ) see so $x= \sqrt[3] 4$ is only solution of problem.

Matematické Fórum

#1 05. 06. 2012 06:04

floor function

#2 05. 06. 2012 10:34 — Editoval vanok (05. 06. 2012 10:41)

Re: floor function

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