Setting the Angular Mode

The angular mode specifies which unit of measure to assume for angles used in trigonometric functions. The mode does not convert numbers already present (see "Conversion Functions" later in this chapter).

360 degrees = 2π radians = 400 grads

To set an angular mode, press Ÿ. A menu will be displayed from which you can select an option.

Option

Description

Annunciator

 

 

 

{}

Sets Degrees mode (DEG). Uses decimal

none

 

degrees, not degrees, minutes, and

 

 

seconds.

 

{}

Sets Radians mode (RAD).

RAD

{}

Sets Grads mode (GRAD).

GRAD

 

 

 

Trigonometric Functions

With x in the display:

 

To Calculate:

Press:

 

 

 

 

Sine of x.

O

 

Cosine of x.

R

 

Tangent of x.

U

 

Arc sine of x.

{M

 

Arc cosine of x.

{P

 

Arc tangent of x.

{S



 

 

 

 

Note

Calculations with the irrational number π cannot be expressed

 

exactly by the 12–digit internal precision of the calculator. This is

 

particularly noticeable in trigonometry. For example, the calculated

 

sin π (radians) is not zero but –2.0676 10–13, a very small

 

number close to zero.

 

 

4–4Real–Number Functions