In order to check whether the given number is a perfect-cube or not, follow the following procedure:-

2. Express the number as a factor of prime numbers.

3. Group the equal factors in triples.

4. After grouping if no factors are left then the given number is perfect cube, otherwise not.

256 = 2 x 128

= 2 x 2 x 64

= 2 x 2 x 2 x 32

= 2 x 2 x 2 x 2 x 16

= 2 x 2 x 2 x 2 x 2 x 8

= 2 x 2 x 2 x 2 x 2 x 2 x 4

= 2 x 2 x 2 x 2 x 2 x 2 x 2 x 2

After grouping the factors of equal triples, 2 x 2 is left.

________________________________________________________________

216 = 2 x 108

= 2 x 2 x 54

= 2 x 2 x 2 x 27

= 2 x 2 x 2 x 3 x 9

= 2 x 2 x 2 x 3 x 3 x 3

We find that the prime factors of 216 can be grouped into triples of equal factor and no factor is left over.

________________________________________________________________

729 = 3 x 243

= 3 x 3 x 81

= 3 x 3 x 3 x 27

= 3 x 3 x 3 x 3 x 9

= 3 x 3 x 3 x 3 x 3 x 3

We find that the prime factors of 729 can be grouped into triples of equal factor and no factor is left over.

• Cube of Numbers

• Perfect Cube

• Properties of Cube

• Cube by Column method

• Cube of Negative numbers

• Cube of Rational numbers

• Cube Root

• Finding cube root by Prime Factorization

• Cube root of Rational numbers

• Estimating cube root

Home Page

GMAT

GRE

1st Grade

2nd Grade

3rd Grade

4th Grade

5th Grade

6th Grade

7th grade math

8th grade math

9th grade math

10th grade math

11th grade math

12th grade math

Precalculus

Worksheets

Chapter wise Test

MCQ's

Math Dictionary

Graph Dictionary

Multiplicative tables

Math Teasers

NTSE

Chinese Numbers

CBSE Sample Papers