Question

finding cube roots by subtract method

Answer 1

Method of successive subtraction to find the cube root:

We Subtract the numbers 1, 7 ,19 ,37, 61, 91, 27 169........ Successively till we get zero.

The number of subtractions will give the cube root of the number.

The number 1, 7, 19, 37, 61, 91, 127, 169....... are obtained by putting n= 1,2,3...... in 1+n×(n-1)×3

For e.g:

Find the cube root of 125

125-1=124

124-7=117

1117- 19=98

98- 37=61

61-61=0

The number of subtractions to get zero is 5

³√125= 5

_____________________________Hope this will help you...