Python tan – Find Tangent of Number in Radians Using math.tan()

To find the tangent of a number (in radians), we can use the Python tan() function from the math module.

import math

math.tan(x)

In Python, we can easily use trigonometric functions with the Python math module. The Python math module allows us to perform trigonometry easily.

With the Python math module, we can find the tangent of a number easily.

To find the tangent of a number, or the sine divided by the cosine of an angle, in radians, we use the math tan() function.

Below is the Python syntax to find the tangent of a number.

import math

math.tan(x)

The input to the tan() function must be a numeric value. The return value will be a numeric value between negative infinity and infinity.

import math

print(math.tan(math.pi/3))
print(math.tan(0))
print(math.tan(math.pi/2))

#Output: 
1.7320508075688767
0.0
1.633123935319537e+16

Converting Degrees to Radians for Input into tan()

The tan() function takes a number in radians as input. If your data is in degrees, you will need to convert the values to radians.

The Python math module has a useful function to convert degrees to radians, the math radians() function.

If we have a value in degrees, we can use radians() to convert the value to radians and then pass it to the tan() function.

import math

print(math.tan(math.radians(60)))
print(math.tan(0))
print(math.tan(math.radians(90)))

#Output: 
1.7320508075688767
0.0
1.633123935319537e+16

Finding the Inverse Tangent of a Number in Python

The Python math module also provides us trigonometric functions to find the inverses of the common trigonometric functions. The atan() function allows us to find the inverse of the tangent of a number.

Below, we show that if we pass a number to tan() and then call the Python atan() function, we get back the same number.

import math

print(math.acos(math.cos(math.pi/3)))
print(math.pi/3)

#Output: 
1.0471975511965976
1.0471975511965976

Finding the Cotangent of a Number in Python

To find the cotangent of a number, we can divide 1 by the tangent of the number.

We can find the cotangent of a number easily with the Python tan() function. You can see how to find the cotangent of a number in the following Python code.

import math

print(1/math.tan(math.pi/3))

#Output: 
0.577350269189626

Hopefully this article has been beneficial for you to understand how to use the math tan() function in Python to find the tangent of a number.