How do you find the cube root of a negative number in Python?

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To find the cube root of a negative number in Python, you can use the cbrt() function from the numpy module or the pow() function from the math module or the ** operator.

Here’s an example of how to use the cbrt() function from the numpy module to find the cube root of a negative number in Python:

import numpy as np

def cube_root(x):
    return np.cbrt(x)

print(cube_root(-8))  # Output: (-2.0+0j)
print(cube_root(-27))  # Output: (-3.0+0j)
print(cube_root(-64))  # Output: (-4.0+0j)

pow() function to find the cube root of a negative number in Python

Here’s an example of how to use the pow() function to find the cube root of a negative number in Python:

import math

def cube_root(x):
    return pow(x, 1/3)

print(cube_root(-8))  # Output: (-2+0j)
print(cube_root(-27))  # Output: (-3+0j)
print(cube_root(-64))  # Output: (-4+0j)

** operator to find the cube root of a negative number in Python

you can also use the ** operator to find the cube root of a negative number in Python. Here’s an example:

def cube_root(x):
    return x ** (1/3)

print(cube_root(-8))  # Output: -2.0
print(cube_root(-27))  # Output: -3.0
print(cube_root(-64))  # Output: -4.0

Cube root of a negative number returns a complex number

Yes, that’s correct. When you try to find the cube root of a negative number in Python, the result is a complex number. This is because a negative number does not have a real cube root, as the cube of a real number is always positive.

For example, when you try to find the cube root of -8 using the cbrt() function from the numpy module, the result is (-2+0j), which is a complex number with a real part of -2 and an imaginary part of 0.

Similarly, when you try to find the cube root of -27 using the pow() function from the math module or the ** operator, the result is (-3+0j), which is a complex number with a real part of -3 and an imaginary part of 0.

To get the real part of the result as a real number, you can use the real attribute of the result. For example:

import numpy as np

def cube_root(x):
    return np.cbrt(x).real

print(cube_root(-8))  # Output: -2.0
print(cube_root(-27))  # Output: -3.0
print(cube_root(-64))  # Output: -4.0
import math

def cube_root(x):
    return pow(x, 1/3).real

print(cube_root(-8))  # Output: -2.0
print(cube_root(-27))  # Output: -3.0
print(cube_root(-64))  # Output: -4.0

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