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asnaseer Group Title

Puzzle: Who can spot what is wrong here? Theorem: 4 = 5 Proof: -20 = -20 16 - 36 = 25 - 45 4^2 - (9x4) = 5^2 - (9x5) 4^2 - (9x4) + 81/4 = 5^2 - (9x5) + 81/4 (4 - 9/2)^2 = (5 - 9/2)^2 4 - 9/2 = 5 - 9/2 4 = 5

  • 2 years ago
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  1. lgbasallote Group Title
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    how did you get -20=-20 from 4=5

    • 2 years ago
  2. Freyes Group Title
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    It's a puzzle.

    • 2 years ago
  3. asnaseer Group Title
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    The Theorem states 4 = 5 It is then followed by the proof

    • 2 years ago
  4. lgbasallote Group Title
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    oh that

    • 2 years ago
  5. Freyes Group Title
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    the third to last step

    • 2 years ago
  6. JakeV8 Group Title
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    sqrt of neg?

    • 2 years ago
  7. asnaseer Group Title
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    and what exactly is wrong with that step?

    • 2 years ago
  8. Freyes Group Title
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    The step is squaring a negative 1/2 and the other is squaring 1/2

    • 2 years ago
  9. asnaseer Group Title
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    which is fine, since (-1/2)^2 = (1/2)^2

    • 2 years ago
  10. Freyes Group Title
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    Yes but then the square root of that after is where the problem is

    • 2 years ago
  11. asnaseer Group Title
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    correct :)

    • 2 years ago
  12. Freyes Group Title
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    you're choosing the positive side

    • 2 years ago
  13. Freyes Group Title
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    not the same negative part you're squaring

    • 2 years ago
  14. cwrw238 Group Title
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    yes - well done frees

    • 2 years ago
  15. asnaseer Group Title
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    it is essentially the same as saying: (-1)^2 = (1)^2 therefore -1 = 1

    • 2 years ago
  16. asnaseer Group Title
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    well spotted!

    • 2 years ago
  17. oldrin.bataku Group Title
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    \[\pm[4-\frac92]=\pm[5-\frac92]\]

    • 2 years ago
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