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The Python cmath.asin() function is used to complete the arc sine of an angle in radians.

The arc sine function is defined as the inverse of a sine function. The domain of the arc sine function is in the range [-1, 1]; every range in this function is obtained in the form of radians.

Syntax

Following is the syntax for the Python cmath.asin() function −

cmath.asin(x)

Parameters

This function contains a numeric value in the range of -1 to 1. If x is greater than 1 or less than -1, then it will generate an error.

Return Value

This function returns the arc sine of x in radians.

Example 1

In the following example, we are finding the arc sine function for the standard values like '0','-1' and '1'cmath.asin().

import cmath
zero = cmath.asin(0)
neg_one = cmath.asin(-1)
pos_one = cmath.asin(1)
print("Arc Sine value of 0:", zero)
print("Arc Sine value of -1:", neg_one)
print("Arc Sine value of 1:", pos_one)

Output

When we run the above code, it produces the following result −

Arc Sine value of 0: 0j
Arc Sine value of -1: (-1.5707963267948966+0j)
Arc Sine value of 1: (1.5707963267948966+0j)

Example 2

Here, we are passing non-standard cosine ratios as arguments, and then arc sine values for these objects are calculated cmath.asin().

import cmath
x = cmath.asin(0.75)
y = cmath.asin(-0.44)
print(x,y)

Output

The result is displayed as follows −

(0.848062078981481+0j) (-0.45559867339582333+0j)

Example 3

In this example, the input is not a complex number. So, we will get a TypeError.

import cmath
cmath.asin("Welcome to TutorialsPoint")

Output

The output is produced is as follows −

Traceback (most recent call last):
  File "/home/cg/root/30462/main.py", line 2, in 
    cmath.asin("Welcome to TutorialsPoint")
TypeError: must be real number, not str

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