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Question 49

Given [1, 2, 3].map(x => x * 2), what is returned?

  1. [2, 4, 6]Correct answer
  2. [1, 2, 3] after in-place doubling
  3. true
  4. undefined

Explanation

map calls the callback for each present element and collects the callback results into a new array, producing doubled values. It does not silently replace the original array unless the program assigns the returned array back.

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Question 49: Given [1, 2, 3].map(x => x * 2), what is returned? · JavaScript Fundamentals · Questena