Formulas and Functions

Table Of Contents

Chapter 12 Trigonometric Functions 327

Function Description

“DEGREES” (page 334) The DEGREES function returns the number of

degrees in an angle expressed in radians.

“RADIANS” (page 335) The RADIANS function returns the number of

radians in an angle expressed in degrees.

“SIN” (page 336) The SIN function returns the sine of an angle that

is expressed in radians.

“SINH” (page 337) The SINH function returns the hyperbolic sine of

the specied number.

“TAN” (page 338) The TAN function returns the tangent of an angle

that is expressed in radians.

“TANH” (page 339) The TANH function returns the hyperbolic

tangent of the specied number.

ACOS

The ACOS function returns the inverse cosine (arccosine) of a number.

ACOS(num)

Â num: A number. num is a number value in the range –1 to 1.

Usage Notes

The ACOS function takes a cosine value and returns a corresponding angle. The Â

resulting angle is expressed in radians, in the range 0 to π (pi). To see the resulting

angle in degrees instead of radians, wrap this function in the DEGREES function;

that is, =DEGREES(ACOS(num)).

Examples

=ACOS(SQRT(2)/2) returns 0.785398163397448, which is approximately π/4.

=ACOS(0.54030230586814) returns 1.

=DEGREES(ACOS(.5)) returns 60, the degree measure of an angle that has a cosine of 0.5.