The Excel SIN Function
Sine of an Angle
For the simple right-angled triangle below, the sine of the angle θ, is the ratio of the opposite side, o, to the hypotenuse, h.
I.e. for the triangle above,
The trig. ratios are discussed further on the Wikipedia Trigonometric Ratios Page
The Excel SIN function calculates the sine of a given angle.
The format of the function is :
SIN( number )
Where the number argument is the angle (in radians), that you want to calculate the sine of.
Converting from Degrees to Radians
If your angle is in degrees, you will need to convert it into radians before supplying it to the Sin function.
The easiest way to do this is to use the Excel Radians function:
=RADIANS( degrees )
An example of this is given below.
Sin Function Examples
Column A of the spreadsheet below, shows examples of the Excel Sin Function, used to calculate the sine of different angles.
|1||=SIN( 0.785398163 )|| - sin of 0.785398163 Radians|
|2||=SIN( PI() / 6 )|| - sin of π/6 Radians|
|3||=SIN( -PI() / 3 )|| - sin of -π/3 Radians|
|4||=SIN( RADIANS( -30 ) )|| - sin of -30 Degrees|
Note that in the above examples:
- In cells A2 & A3, the Excel Pi function is used to supply the values π/6 and -π/3;
- In cell A4, the Excel Radians function is used to convert the angle of -30 degrees into radians before it is supplied to the Sin function.
Further information and examples of the Excel Sin function can be found on the Microsoft Office website.