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Find the first 5 terms in the sequence from the explicit formula: an=(-2)^n-1

A: -2,-4...
B: -1, -2...
C: 2, -4...
D: 1, -2...

User BiNZGi
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1 Answer

6 votes

Answer:

D

Explanation:

Substitute n = 1, 2, 3, 4, 5 into the explicit formula

a₁ =
(-2)^(0) = 1

a₂ =
(-2)^(1) = - 2

a₃ =
(-2)^(2) = 4

a₄ =
(-2)^(3) = - 8

a₅ =
(-2)^(4) = 16

The first 5 terms are 1, - 2, 4, - 8, 16

User Lauri Elias
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