These functions operate on numbers and require numeric expressions as arguments. All trigonometric functions use radians as the unit of measurement. Once you have obtained a result, you can convert the radians into degrees using the DEGREES function.

	ACOS (Arc Cosine)
	ASIN (Arc Sin)
	ATAN (Arc Tangent)
	ATAN2 (Arc Tangent 2)
	COS (Cosine)
	DEGREES
	RADIANS
	SIN (Sine)
	TAN (Tangent)

ACOS (Arc Cosine)

Calculates the arc cosine (the inverse of cosine) and returns the corresponding angle in radians, in the range 0 to pi.

Format: =ACOS(number)

Argument:

•	number: a cosine value or a simple operation that yields a cosine. Valid range is -1.0 to 1.0.

Example: =ACOS(5/7) calculates the arc cosine of 5/7 (cosine 0.7143) and returns 0.7752 (radians).

ASIN (Arc Sine)

Calculates the arc sine (the inverse of sine) and returns the corresponding angle in radians, in the range -pi/2 to pi/2.

Format: =ASIN(number)

Argument:

•	number: a sine value or a simple operation that yields a sine. Valid range is -1.0 to 1.0.

Example: =ASIN(1) calculates that the arc sine of 1 is pi/2 radians (90 degrees), and returns 1.570 (radians).

ATAN (Arc Tangent)

Calculates the arc tangent (the inverse of tangent) and returns the corresponding angle in radians, in the range -pi/2 to pi/2.

Format: =ATAN(number)

Argument:

•	number: a tangent value or a simple operation that yields a tangent

Example: =ATAN(1) calculates that the arc tangent of 1 is pi/4 (45 degrees), and returns .785 (radians).

ATAN2 (Arc Tangent 2)

Calculates the angle between the positive x-axis and a line that starts at the origin (0,0) and passes through the x and y coordinates you specify, and returns the angle in radians, in the range -pi to pi.

Format: =ATAN2(x number,y number)

Arguments:

•	x number: an x-coordinate value
•	y number: a y-coordinate value

Example: =ATAN2(1,1) determines that the angle between the positive x-axis and the line that passes through the coordinates (1,1) is 45 degrees, and returns .785 (radians).

COS (Cosine)

Calculates the cosine of a number, where the number is an angle in radians.

Format: =COS(number)

Argument:

•	number: a numeric value or expression in radians

Example: =COS(1.0472) returns 0.5, the cosine of 1.0472 radians (60 degrees).

DEGREES

Converts the number of radians to an angle in degrees.

Format: =DEGREES(radians number)

Argument:

•	radians number: a numeric value in radians

Example: =DEGREES(PI()) returns 180 (pi radians = 180 degrees).

RADIANS

Converts the number of degrees to radians, the standard unit used for trigonometric functions.

Format: =RADIANS(degrees number)

Argument:

•	degrees number: a numeric expression

Example: =RADIANS(90) returns 1.5708 (90 degrees = 1.5708 radians).

SIN (Sine)

Calculates the sine of a number, where the number is the angle in radians.

Format: =SIN(number)

Argument:

•	number: a numeric value or expression in radians

Example: =SIN(radians(30)) returns 0.5, the sine of 30 degrees.

TAN (Tangent)

Calculates the tangent of a number, where the number is the angle in radians.

Format: =TAN(number)

Argument:

•	number: a numeric value or expression in radians

Example: =TAN(radians(45)) returns 1, the tangent of a 45-degree angle.

Related topic

Alphabetical list of functions