# Python - How To Square Root in Python

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For a given number, its square root is a number whose square is equal to this number.

In Python, we can calculate the square root of a number using built-in functions and operators, which will be discussed in this tutorial.

## Use the math.sqrt() to Calculate the Square Root of a Number in Python

The math module has different functions to perform mathematical operations in Python. The sqrt() function returns the square root of a positive number. For example:

import math print(math.sqrt(16))

Output:

4.0

We can also calculate the square root of a list of numbers using this function. We iterate through the list using a for loop and apply the math.sqrt() function to each element. See the below example code.

import math  a = [4,2,6] b = []  for i in a:     b.append(math.sqrt(i)) print(b)

Output:

[2.0, 1.4142135623730951, 2.449489742783178]

## Use the pow() Function to Calculate the Square Root of a Number in Python

The square root of a number is nothing but the number raised to power 0.5. The pow() function in Python returns the value of a number raised to some specified power and can be used to calculate the square root of a number as shown below. The first parameter of the pow() function is the base, and the second one is the exponent.

print(pow(9,0.5))

Output:

3.0

## Use the ** Operator to Calculate the Square Root of a Number in Python

The ** operator performs the same function as the pow method. We can use it to calculate the square root of a number as shown below.

print(9 ** (0.5))

Output:

3.0

## Use the cmath.sqrt() to Calculate the Square Root of a Number in Python

The cmath module has methods to deal with complex numbers. The cmath.sqrt() returns the square-root of negative or imaginary numbers. For example:

import cmath  x = -16 print(cmath.sqrt(x))

Output:

4j

## Use the numpy.sqrt() Method to Calculate the Square Root of a Number in Python

can calculate the square root of all the elements in a data object like a list or an array at once. It returns an array that contains the square root of all the elements. For example:

import numpy as np  a = [4,2,6] print(np.sqrt(a))

Output:

[2.         1.41421356 2.44948974]