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    Find the positive value of ​12+12+12+12+…\sqrt{12 + \sqrt{12 + \sqrt{12 + \sqrt{12 + \dots}}}}12+12+12+12+…​​​​​​
    Question

    Find the positive value of
    12+12+12+12+\sqrt{12 + \sqrt{12 + \sqrt{12 + \sqrt{12 + \dots}}}}​​

    A.

    12

    B.

    2

    C.

    3

    D.

    4

    Correct option is D

    Given:

    12+12+12+12+\sqrt{12 + \sqrt{12 + \sqrt{12 + \sqrt{12 + \dots}}}}​​

    Solution:

    12+12+12+12+\sqrt{12 + \sqrt{12 + \sqrt{12 + \sqrt{12 + \dots}}}}​ =y

    y = 12+y

    Squaring on both sides

    y2  = 12 + y

    y2 - y - 12 = 0

    y2 - 4y + 3y - 12 = 0

    y(y - 4) + 3(y - 4) = 0

    (y - 4)(y + 3) = 0

    y = 4 or y = -3

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