Perfect cube

Which of the following number is not a perfect cube?
a. 64
b. 729
c. 800
d. 1331

Correct answer:

x =  800

Step-by-step explanation:

$$\begin{gathered} a_1=\sqrt[3]{64}=4 \\ {b}_1=\sqrt[3]{729}=9 \\ {c}_1=\sqrt[3]{800}\doteq 9.2832 \\ {d}_1=\sqrt[3]{1331}=11 \\ {c}_1\mathrm{\notin }N \\ 800=2^5\times 5^2\mathrm{\ne }{n}^3 \\ x=800=800 \end{gathered}$$

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Dr Math

A perfect cube is a number that is obtained by multiplying the same integer three times (so its third power of integer).

25 days ago  Like

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