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1 vote
Find the eighth term of the following geometric sequence 14,-7, 7/2

User Vkt
by
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2 Answers

5 votes

You can see that you get the next term by dividing by 2 and switching sign (that is, dividing by -2).

So, the general term is


a_n = (14)/((-2)^(n-1))

In fact, you can check that


a_1 = (14)/((-2)^0)=(14)/(1)=14


a_2=(14)/((-2)^1)=(14)/(-2)=-7


a_3=(14)/((-2)^2)=(14)/(4)=(7)/(2)

So, the eight term is


a_8=(14)/((-2)^7)=(7)/(-2^6)=-(7)/(64)

User Thorsten Hans
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5.0k points
5 votes
7/32
Keep the pattern going. A(n)=A(n-1)*-1/2
14, -7, 7/2, -7/4, 7/8, -7/16, 7/32
User Andrei LED
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5.0k points