AT&T 6300 Programmer's Manual page 219

Syntax
Remarks
Example
COS
Function
Returns the cosine of the argument.
COS (numexp)
The argument "numexp" represents the angle
in radians.
The calculation of the COS function is
performed in single precision, unless "ID" is
supplied in the GWBASIC command line.
10 X=2*COS(.4]
20 PRINT X
RUN
1.842122
Ok
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