Beginner's Programming Tutorial in QBasic

Example:
CONST PI = 3.141593
PRINT COS(PI / 4)
PRINT SIN(PI / 3)PRINT TAN(-PI / 2)
PRINT ATN(TAN(-PI / 2))
Output:
.7071067.8660254

(^6137956) 1.570796 (Same as PI / 2)