Objective

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6.8A-Geometric Sequence

• Objective TSW use geometric sequences.

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Vocabulary for sequences
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Geometric Sequence has a common ratio r which
is multiplied to each previous term.

• To find missing terms same as an arithmetic
  sequence, but just a different formula since we
  are multiplying instead of adding to previous
  terms.
• Remember to use your order of operations when
  solving (PEMDAS)
• Plug what you know into the following formula
• an a1r(n-1)

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Examples Write an equation for the nth term of a
geometric sequence. Remember an and n stay in
the equationthey are your x and y!

• 1. 0.5, 2, 8, 32, 2. a4 5, r 6

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You Try!

• 3. -0.25, 2, -16, 128, 4. a3 16, r 4

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Find the indicated term for the geometric
sequence.

• 5. a1 800, r 1/2 , n 6 6.

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7. Find two geometric means between 2 and 54
-2, ____, ____, 54
-2
54
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NA
x
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Homework

• Pgs. 700-702 s 19-39(odds), 78-80(all)