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Please help!!! If the first 4 terms of a geometric sequence are...

Please help!!! If the first 4 terms of a geometric sequence are...-example-1
User CivFan
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1 Answer

5 votes

Answer:

c.) aₙ = 5 × 4ⁿ⁻¹

Step-by-step explanation:

Geometric sequence: aₙ = a(r)ⁿ⁻¹

where 'a' resembles first term of a sequence, 'r' is the common difference.

Here sequence: 5, 20, 80, 320,...

First term (a) = 5

Common difference (d) = second term ÷ first term = 20 ÷ 5 = 4

Hence putting into equation: aₙ = 5(4)ⁿ⁻¹

User CyberPunk
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