Try

? 256^(1/4)
* or in general
? lnVal ^ (1/lnPower)

>Did Visual Foxpro have any function like below
> Beside of SQRT() Function .
>
> SQRT WITH POWER ,
> _____
> 4 /256
> /
>
> = 4
>
> Because i'm having problem on calculation which need to apply that function
>
> Thank you