Root √ problem

Question

So I made a basic calculator which can do + - * / ^ √ with 2 numbers can be chosen by user. They all worked perfectly fine except the √. Well in this calculator, any root numbers (odd and even number) of a negative number can't be solved on this calculator, which is not true (Example: square root (√) of -4 or fourth root (4√) of -16 is indeed can't be solved but cubic root (3√) of -64 or fifth root (5√) of -1024 can be solved but in this calculator it is not possible) (I used a way to make "custom" root number beside square or cubic root: "pow(x , 1/y)" ). Summary: Odd root number of negative numbers can be solved but in this calculator it just doesn't do it. So i want to know if there is any way to fix this. Here goes the code:
https://code.sololearn.com/cs2saqeQUvLH/?ref=app

Answer 1

Did you take into account that roots for negative numbers work very differently from roots for positive numbers? E.g. you need imaginary numbers.

Answer 2

Simon Sauter
Well I tested again with cubic root of -10 and as result it say "-nan" but cubic root of 10 still has a valid result tho
Test I tried:
-Cubic root of 10 = valid (true)
-Cubic root of -10 = "-nan" (false)
-Square root of 10 = valid (true)
-Square root of -10 = "-nan" (true)
Well I don't know about how numbers work in C++ like how negative numbers are different from positive ones