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Lv 6
? asked in Science & MathematicsMathematics · 6 years ago

What is the infinite sum of 1+(-1)+1+(-1)+...?

a) 1

b) 0

c) 1/2

Please justify your answer.

4 Answers

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  • xyzzy
    Lv 7
    6 years ago
    Favorite Answer

    d) none of the above... the series does not converge.

    by most rules, the correct answer is that the series doesn't converge. But there are ways to bend the rules and get 1/2

  • ?
    Lv 7
    6 years ago

    c) 1/2

    It never reaches infinity, so it's never a complete sum. The process used to arrive at 1/2 is called Abel Summation.

  • ?
    Lv 7
    6 years ago

    i Interval[{-(1/2), 1/2}] + Interval[{0, 1}]

  • ?
    6 years ago

    b - Common Sense

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