COS Excel function is an inbuilt trigonometric function in excel which is used to calculate the cosine value of given number or in terms or trigonometry the cosine value of a given angle, here the angle is a number in excel and this function takes only a single argument which is the input number provided.

**Syntax**: =COS (number)

The COS function syntax has the following arguments:

**number**– an angle in radians for which we want the cosine- If an angle is given in degrees, convert it to radians by using the RADIANS function or multiplying the angle by PI()/180

**Example**: Let’s look at some Excel COS function examples and explore how to use the COS function as a worksheet function in Microsoft Excel:

**Syntax**: =COS(I65)

**Result**:

Based on the Excel spreadsheet above, the following COS examples would return:

**Syntax**: =COS(I66)**Result**: 0.965873885

**Syntax**: =COS(I67)**Result**: 0.877582562

**Syntax**: =COS(I68)**Result**: 0.808027508

**Syntax**: =COS(I69)**Result**: 0.540302306

**Syntax**: =COS(I70)**Result**: 0.070737202

**Syntax**: =COS(I71)**Result**: -0.079120889

**Syntax**: =COS(I72)**Result**: -0.416146837