Commodore VIC-20 Programmer's Reference Manual page 59

See the ASC function for ASCIMo-numeric conversion.
COS
Format: Abbreviation: Screen Display:
COS(X) None None
Action: Returns the cosine of X in radians. The calculation of
COS(X) is performed in floating point binary.
EXAMPLE:
10X = 2*COS(.4)
20 PRfNT X
RUN
1.84212199
READY.
Abbreviation: Screen Display:
Effl
Action: Returns e to the power of X.X must be <= 88.02969191. If
EXP overflows, the "OVERFLOW" error message is displayed.
EXAMPLE:
10 X = 5
20 PRINT EXP (X-1)
RUN
54.5981501
READY.
Abbreviation: Screen Display:
fQ ^
Action: Arguments to FRE are dummy arguments. FRE returns the
number of bytes in memory not being used by BASIC.
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