+---------------------------------+
|              ACOS               |
+---------------------------------+
ACOS(<expN>)

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Returns (in radians) the arc cosine of <expN>.
Return value - Numeric
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This trigonometric function returns the arc cosine of <expN>, an angle
in radians between 0 and +pi (3.14159).  The value of <expN> may range
between +1 and -1.

To convert the angle returned by ACOS() to degrees use the RTOD()
function.  The number of decimal places ACOS() returns is determined by
the SET DECIMALS command.

+---------------------------------+
|            Examples             |
+---------------------------------+
? RTOD(ACOS(0))

STORE -1 to arcangle
? RTOD(ACOS(arcangle))

? RTOD(ACOS(sqrt(2)/2))

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See Also:  COS(), RTOD(), SET DECIMALS

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