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GlobalFunctionsisNaNbeginner

isNaN — numeric input

📖 Usage Example
isNaN(42)     // → false
isNaN(3.14)   // → false

isNaN() returns false for any valid numeric value.

isNaN with Number

isNaN(42) returns false.

Challenge: Verify that isNaN(42) === false.

💡 Hints (1)
  • • isNaN(42) is false because 42 is a valid number.