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Cube Root of perfect cubes

In vedic maths the technique of cube root is simply so amazing that the students will be able to correctly predict the cube root of a number just by looking at it.

What is cube rooting?

Cubing is multiplying and number by itself and then multiplying answer by the original number once again.

Thus the cube of 2 is 2 X 2 X 2 Answer is 8 represented as 2³

The cube of 3 is 3 X 3 X 3 Answer is 27 is represented as 3³

In squaring we multiply the number by itself and in cubing we multiply the number twice by itself.

What Cube Rooting is?

From the above example number 8 is the cube of 2 and number 2 is the cbe root of 8.

Similarly number 27 is the cube of 3 and 3 is the cube root of 27.

In this chaper of cube rooting we are to learn to calculate cube root. If you are given number 8, you are to arrive at 2. this is a very simple but we will calculate higher order numbers like 744969, 275616

The technique provided here is to calculate the perfect cubes only. It can not be used to find imperfect cubes.

To use this technique, first you must know the number is a perfect cube.

Method:

Memorize the list table below ;

NUMBER	CUBE
1	1
2	8
3	27
4	64
5	125
6	216
7	343
8	512
9	729
10	1000

See the above table,the cube of 1 is 1, 2 is 8 and 3 is 27 and so on

Memorize this list. Now give your attention to the underlined numbers.These numbers have unique relationship amongst themselves..

In the first row, the underlined numbers are 1 and 1. It extablish that if the last digit of the cube is 1 then the last digit of the cube root is also 1.

In the second row the underlined numbers are 2 and 8. It establishes relationship that if the last digit of cube is 8 then the last digit of the cube root is 2. Remember if the last digit of the number is 8 the last digit of its cube-root will always be 2.

Similarly thrd row - if the last digit of cube is 7 then the last digit of the cube-root is 3.

In the last row, when a cube ends in 0, the cube-root also ends in 0.

The Last Digit of the Cube	The last Digit of the Cube Root
1	1
2	8
3	7
4	4
5	5
6	6
7	3
8	2
9	9
0	0

From the above table we cab conclude that all cube roots end with the same number as their correspoding cubes except for pairs of 3 & 7 and 8 & 2 which end with each other.

Also keep in mind that whenever you calculate cube root, you must put a slash before last three digits.

If you are find the cube root of 105925 and this 45932 you will write it as 105/925 and 45/932.

Immaterial of the number you will alway put slash before last three digits.

LET US SOLVE CUBE ROOTS