What is the sum of the first eight terms of the geometric series 2 + 6 + 18 + 54+ …? 510 3,280 6,560 4,374

Question

What is the sum of the first eight terms of the geometric series 2 + 6 + 18 + 54+ …? 510 3,280 6,560 4,374

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Nick 5 years 2021-08-03T18:09:30+00:00 2 Answers 27 views 0

Answers ( )

  1. bonexptip
    0
    2021-08-03T18:11:16+00:00
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    Answer:

    6,560

    Step-by-step explanation:

  2. sori
    0
    2021-08-03T18:11:19+00:00
    Reply

    Answer:

    6,560

    Step-by-step explanation:

    We are given the first four terms of the sequence:

    2, 6, 18, 54, …

    We need to find another four terms to find the sum.

    I don’t know how to explain how I got the pattern but you have to multiply by 3:

    2 * 3 = 6

    6 * 3 = 18

    18 * 3 = 54

    To find the next term, we will multiply 54 by 3:

    54 * 3 = 162

    2, 6, 18, 54, 162, …

    We now have 5 terms.

    Next, multiply 162 by 3:

    162 * 3 = 486

    2, 6, 18, 54, 162, 486, …

    We now have 6 terms.

    Next, multiply 486 by 3:

    486 * 3 = 1458

    2, 6, 18, 54, 162, 486, 1458, …

    We now have 7 terms.

    Lastly, multiply 1458 by 3:

    1458 * 3 = 4374

    2, 6, 18, 54, 162, 486, 1458, 4374, …

    We now have the first 8 terms.

    Now, we add all these numbers together:

    2 + 6 + 18 + 54 + 162 + 486 + 1458 + 4374 = 6560

    The sum of the first eight terms of the geometric sequence is 6,560

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Giải phương trình 1 ẩn: x + 2 - 2(x + 1) = -x . Hỏi x = ? ( )