Roman C. answered 10/22/12
Masters of Education Graduate with Mathematics Expertise
And if the number is not a perfect cube, you can try different decimals and adjust until you get an accurate enough approximation or us a special algorithm.
If you just need to simplify cube-root expressions yo just need to find the largest cube y3 that is a factor of n and write n = y3x. Then Cuberoot[n] = y*Cuberoot[x]. Example: Cuberoot[192] = Cuberoot[64*3] = Cuberoot[43*3] = 4*Cuberoot[3].
--------------------------------------------------
Example of the nth root algorithm applied to approximating cube-root of 75834.632
See if you can follow this:
4 2. 3 2 ...
75834.632000000...
64 = 4^3
11834
10088 = 423-403
1746632
1598967 = 4233-4203
147665000
107408168 = 42323-42303
40256832 etc.