# Python program to find the square root

By Lenin Mishra

#### Square root of Positive Numbers

Code

``````num = 4

sqrt_num = num ** 0.5
print(f"Square root of {num} is {sqrt_num}")``````

Output

``Square root of 4 is 2.0``

#### Square root of Positive numbers - through User Input

Code

``````num = input("Enter a number: ")

sqrt_num = float(num) ** 0.5
print(f"Square root of {num} is {sqrt_num}")``````

Output

``````Enter a number: 9
Square root of 9 is 3.0``````

Now be careful with this method. We are using the `input()` built in function of Python. Since it returns a string, we convert the string into number using the `float()` function. Then, the square root is calculated.

Using the built in `int()` function will chop off the decimal places.

#### Square root of Complex Numbers

Code

``````import cmath

num = 3+5j

sqrt_num = cmath.sqrt(num)
print(f"Square root of {num} is {sqrt_num}")``````

Output

``Square root of (3+5j) is (2.101303392521568+1.189737764140758j)``

#### Square root of Complex Numbers - through user input

Code

``````import cmath

user_input = input("Enter a complex number: ")
num = eval(user_input)

sqrt_num = cmath.sqrt(num)
print(f"Square root of {num} is {sqrt_num}")``````

Here we are using the `eval()` built in function in Python instead of `float()` to convert user input string to complex numbers.

Output

``````Enter a complex number: 2+3j
Square root of (2+3j) is (1.6741492280355401+0.8959774761298381j)``````

All the above codes use f-strings. Learn about python f-strings here.