How do you calculate cube root?

Answer 1

unless it is a perfect cube one cannot do cube roots by hand without knowing calculus. Perfect cubes are easy to recognize with a bit of practice. one knows that 3*3*3 is 27 therefore the cube root of 27 is 3

This is a very easy method in your head in minutes.

You need a perfect cube.

First, you need to learn the cubes of nos 1-9.

(Ten is easy so no need to mention.)

They are

1-1

2-8

3-27

4-64

5-125

6-216

7-343

8-512

9-729

If you notice, each cube ends with a different number.Then, follow what is written below.

eg.970299

1)Split it into parts with 3 nos in it. 970 299

2)Take the group to the right.

See what it ends with. Compare it with the cube from 299=729=9

1-10. That is the last digit of the cube root.

3)Take the first group and see between which cubes it 970=between

lies. 729 & 1000 (9 & 10)

Take the smaller no. That is the first digit.

Thus 99 is the cube root of 970299.

You can check. This works till every number till 1 million.