QBasic provides several functions to do mathematical calculations. A few of them are discussed here.
Use SQR to find the "square root" of a number.
ABS returns the absolute value of a number. In other words, ABS converts a negative number to a positive number (if you pass a positive number, ABS does nothing).
COS, SIN, TAN, and ATN
You can do the following trigonometric functions in QBasic:
ATN (Arctangent, inverse of TAN)
PRINT COS(PI / 4)
PRINT SIN(PI / 3)
PRINT TAN(-PI / 2)
PRINT ATN(TAN(-PI / 2))
1.570796 (Same as PI / 2)
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