FIGURES REPRESENTING THE PROCESSES OF FINDING CUBE ROOT

Thus, 289383 will be pointed off into two periods—289·383—and we readily see there will be only 2 figures in the root.

The simplest method of finding the cube root of numbers whose prime factors are not known is analogous to the method of finding square root, being based upon the form of the cube of the sum of two numbers.

Explanation: The cube root of 1728 is 12. Let us see how we found it.

12 = 1 ten + 2 units

123= (10 + 2)3

(10 + 2)3 means 10 + 2 × 10 + 2 × 10 + 2

10+2
10+2
102+(10 × 2)
+(10 × 2)+22
102+2(10 × 2)+22
10+2
103+2(102 × 2)+(10 × 22)
+(102 × 2)+2(10 × 22)+23
103+3(102 × 2)+3(10 × 22)+23