# 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] ``