Angles are applied in two primary modes: degrees and radians. Set the mode accordingly.
Warning Most calculator errors in trigonometry occur because the calculator is in the wrong mode.
To set the angle mode, press MODE. Then navigate to Angle and select either RADIAN or DEGREE mode. In the examples below, the Exact/Approx mode is set to AUTO. Press ENTER to return to the home screen.
Degree Mode
In degree mode, angles can be entered as decimal degrees (DD) or degress-minutes-seconds (DMS). For example, to evaluate tan(17°43'25''), press
(located above T ) (located above T) ' (located above = ) '' (located above 1 ) |
Press (located above the ENTER key) to obtain a decimal approximation.
While in degree mode, you can convert radians to degrees. For example, to convert 1.23 radians to degrees, press
MATH (located above 5) (to select 2: Angle) (to select 2:' ) [Hence, 1.23' 70.4738°.] |
Radian Mode
Set the calculator to RADIAN mode. Radian angles can then be entered as ordinary numbers. For example, to evaluate
, press
(located above Y ) (located above ) |
The exact answer, is displayed. Press to get a decimal approximation.
While in radian mode, you can convert degrees to radians. Enter the angle using the DMS symbols. For example, to convert 17°43'25" to radians, press
(located above | ) ' (located above = ) '' (located above 1 ) (located above the key) |