Question

using the method of successive subtraction examine whether or not the following numbers are perfect cubes first one 132nd 13521 782481 1331

Answer 1

Step-by-step explanation:

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