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Degrees, Radians, and Trig Angle Entries
Remember: The calculator defaults to Radian measure.
 

Working with Degrees:

There are two ways to engage "Degrees" when working with the calculator:
1.  Set the MODE to Degree and all further calculations will be in degrees.
2.  If in Radian MODE, use the Degree Symbol (2nd APPS (Angle) and select #1 ° ).
Note: The degree status will be applied to that one calculation only.  All other calculations
will return to radian mode.
 

Converting Degrees to Radians:

Find the radian measure of an angle whose measure is 500°.

Method 1: (in Radian or Degree mode)
 Convert by multiplying by  1.

Mode set to Radian
2
Method 2:  (in Radian mode)

With the mode set to Radian, type 500°.  Notice the degree symbol. 
Hit Enter.

NOTE:  If in Degree mode, you can force an answer to radians by using
2nd APPS(Angle) #3 r.

In Degree mode,
but ......

3
gives the answer 0.0548036651
(WRONG!!!)

4
 gives the correct answer of 0.
 

 

Converting Radians to Degrees:

Find the degree measure of an angle whose measure is 5. 

Method 1: (in Radian or Degree  mode)
 Convert by multiplying by  6.

Mode set to Degree7
Method 2:  (in Degree mode)
In Degree mode, the r symbol can be used to convert radians to degrees.  The r is found 2nd APPS(Angle) #3 r. 

With the mode set to Degree, type 8

 

Convert 57° 45' 17'' to decimal degrees:

In either Radian or Degree Mode:    Type 57° 45' 17'' and hit Enter.
    °   is under Angle (above APPS) #1
    '   is under Angle (above APPS) #2
    ''   use ALPHA (green) key with the quote symbol above the + sign.     Answer: 57.75472222
 

Convert 57° 45' 17'' to radians:

With the mode set to Radian:    Type 57° 45' 17'' °  and hit Enter.         Answer:  1.008010061
  ** Note the use of the additional degree symbol at the end.  Without it, conversion would be to decimal degrees, even though the mode is set to radians.
 

Convert 48.555° to degrees, minutes, seconds:

Type 48.555 ►DMS         Answer:  48° 33' 18''
 The ►DMS is #4 on the Angle menu (2nd APPS).  This function works even if Mode is set to Radian.
 

Given cos A = .0258.  Find ∠A expressed in degree, minutes, seconds.

With the mode set to Degree:  Type cos-1(.0258).  Hit Enter.
Engage ►DMS       Answer:  88° 31' 17.777''  
(Be careful here to be in the correct mode!!)
 

Find sin 57° 45' 17'':

Enter sin(57° 45' 17'' °).   This problem is clearly dealing with degrees.  The entry shown here works even if MODE is set to Radian.         Answer:  .8457717984
If MODE is set to Degree, the degree symbol at the end is not needed.

 

Find cos(-250° 21'):

Enter cos (-250° 21' °) when in Radian mode.        Answer:  -.3362735421
If MODE is set to Degree, the degree symbol at the end is not needed.

 

Find sec(25° 40'):

There is no key for secant.  But, since  10, enter:  1/cos(25° 40' °) when in Radian mode.   If MODE is set to Degree, the degree symbol at the end is not needed.
Answer:  1.109472591

 

Find  11:

Enter directly:  12  when in Radian mode.    Answer:  -.7660444431
If in Degree mode, enter  13.

 

Find  14:

There is no key for cosecant.  But, since  15, enter:  16 when in Radian mode.   Answer:  1.015426612

In Degree mode, enter   17.

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