Math.pow(n,0.5)
sqrt(2)
root(n,2)
n**0.5
etc.

Input:
sqrt(4) //you can call your function whatever you want
Output:
2
Input:
7
Output:
2.645751
Input:
5.0625
Output:
2.25
Input:
-15
Output:
3.872983i
Input:
-9
Output:
3i