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Prove that there is no n ∈ ℕ such that n² = 2

User Momergil
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Final answer:

To prove that there is no n ∈ ℕ such that n² = 2, we can use a proof by contradiction. The assumption that an n exists leads to a contradiction when considering the polynomial equation x^4 - 4 = 0. By checking all possible rational roots, we can conclude that there is no solution.

Step-by-step explanation:

To prove that there is no n ∈ ℕ such that n² = 2, we can use a proof by contradiction.

  1. Assume that there exists an n ∈ ℕ such that n² = 2.
  2. Square both sides to get n^4 = 4.
  3. By rearranging the equation, n^4 - 4 = 0.
  4. Now, consider the polynomial equation x^4 - 4 = 0.
  5. Using the rational root theorem, we can see that the only possible rational roots are ±1 and ±2.
  6. By substituting these values into the equation, we find that none of them satisfy the equation.
  7. Therefore, there is no n ∈ ℕ such that n² = 2.

User Himerzi
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