Testing DEF FN (User-Defined Functions)
========================================

Test 1: FN SQUARE(5) = 25 (expected: 25)
        FN SQUARE(10) = 100 (expected: 100)

Test 2: FN ADD(3, 7) = 10 (expected: 10)
        FN ADD(100, 50) = 150 (expected: 150)

Test 3: FN CIRCLE(5) = 78.53975 (area of circle r=5)
        FN CIRCLE(10) = 314.159 (area of circle r=10)

Test 4: FN QUAD(5) = 20 (expected: 20)

Test 5: FN GREET$("World") =
        Hello, World!

Test 6: FN MAX%(10, 20) = 20 (expected: 20)
        FN MAX%(50, 30) = 50 (expected: 50)

Test 7: FN DEGREES(1.5708) = 90.00024264 (~90 degrees)

Test 8: 10 + FN CUBE(3) = 37 (expected: 37)

Test 9: FN AVG(10, 20) = 15 (expected: 15)
        FN AVG(5, 15) = 10 (expected: 10)

Test 10: FN F1(10) = 11 , FN F2(10) = 12 , FN F3(10) = 13 

DEF FN tests complete!

