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## Angles

### Entering Angles

Angles are their own object type. An angle is entered by prefixing a number with the angle symbol (∡, **AL-RS-6**), followed by a number, then finally a suffix that indicates the system (° = degrees, r = radians, g = grads, or d = DMS [DDD.MMSS, where DDD=degrees, MM=minutes, SS=seconds])^{1)}. To enter an angle in the current angle mode of the calculator, the suffix can be left off. For example, the following all indicate an angle of 90.5 degrees:

`∡90.5°`

`∡1.5795.r`

`∡100.5556g`

`90.3000d`

and

`∡90.5`

with the angle mode set to degrees.

### Working with Angles

Trigonometric functions operate on angle objects as expected:

`∡45° SIN`

yields the real number result `0.7071.`

Basic arithmetic operations can also be applied to angle objects:

`∡90° ∡50° +`

yields `∡135°`

`∡1.57r ∡50° -`

yields `∡0.6973r`

`∡90° ∡45° *`

yields `4050`

`∡90° ∡45° /`

yields `2`

The result of an operation on angle objects has the following conventions:

- Addition and subtraction between angles returns an angle expressed in the system of the first argument,
- For all other operations, angles will be converted to the current angle mode and output a number.

### Commands for Angle Objects

^{1)}