Purpose
Return value
Syntax
=SIN(number)- number - The angle in radians for which you want the sine.
How to use
The SIN function returns the sine of an angle provided in radians. In geometric terms, the sine of an angle returns the ratio of a right triangle's opposite side over its hypotenuse. For example, the sine of PI()/6 radians (30°) returns the ratio 0.5.
=SIN(PI()/6) // Returns 0.5
Using Degrees
To supply an angle to SIN in degrees, multiply the angle by PI()/180 or use the RADIANS function to convert to radians. For example, to get the SIN of 30 degrees, you can use either formula below:
=SIN(30*PI()/180)
=SIN(RADIANS(30))
Explanation
The graph of sine, shown above, visualizes the output of the function for all angles from 0 to a full rotation. The function is periodic, so after a full rotation, the output of the function repeats. Geometrically, the function returns the y-component of the point corresponding to an angle on the unit circle. The function's output will always be in the range [-1, 1].
Graph courtesy of wumbo.net.
Related functions
COS Function
The Excel COS function returns the cosine of an angle given in radians. To supply an angle to COS in degrees, use the RADIANS function to convert to radians.
TAN Function
The Excel TAN function returns the tangent of the angle given in radians. To supply an angle to TAN in degrees, multiply the angle by PI()/180 or use the RADIANS function to convert to radians.
RADIANS Function
The Excel RADIANS function converts degrees to radians. For example, =RADIANS(180) returns 3.1415 or the value of π (pi)....
ASIN Function
The Excel ASIN function returns the inverse sine of a number.
