Maths - Geometric Progression

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The second term of a GP is 1/2 and the sum ti infinity of the series is 4. Find the first term and and the common ratio of the series.

  • Maths - Geometric Progression -

    ar = 1/2
    a/(1-r) = 4

    a = 2-√2
    r = 1/4 (2+√2)

    or

    a = 2+√2
    r = 14 (2-√2)

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