Question

How do you find the cube root of a number?

Answer 1

first find the prime factorization of the number

Answer 2

look for number closed by which has easy cube roots

\[(28)^{1/3}\]

\[(27)^{1/3}+(1/3)(27)^{-2/3}(1)\]=3.04

Answer 3

thanks! i think im basically done now... :)

Answer 4

How would that work if the desired number you wish to find the cube root is itself a prime number? Looks like logs would be a method.

Answer 5

No that's what i do...
if i have options i multiply them

Answer 6

1. Calculator
2. Longhand method.
Example: Find the cube root of 1000.57.
Seperate into groups of three from the decimal dot:
1|000|.57
We do it like a division problem.
the cube root of 1 is 1.
subtract 1 from 1, leaving zero.
then, find the largest x that fulfills
300A^2+30Ax+x^2
where A is the previous answer (1)
300+30x+x^2
in this case, it is zero.
Write the 0 above the radical.
Our answer now is 10.
Now we continue to do this.
note that .37 becomes 370.
our remainder is 370.
300A^2+30Ax+x^2
30000+300x+x^2
again, find the largest x that can be
in this case, zero again.
Keep on going until the answer has the desired accuracy.

Answer 7

you dont look for easy numbers, how about the number is given?