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191 19 Mars
Find the term to term rules for the following sequences:

b)
2, 6, 18, 54, 162

User Vulpo
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1 Answer

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13 votes

Answer: Please see explanation column for answer

Explanation:

According to sequence 2, 6, 18, 54, 162

--we can see that it is a geometric sequence since to go from one term to the next requires us to multiply by 3 which is called the common ratio which is gotten by dividing the next by the previous.

ie term 2/ term 1= 6/2 = 3

term 3/ term 2= 18/6= 3

term 4/ term 3= 54/28= 3

term 5 / term 4= 162/54=3

term 6 will therefore be 162 x3 = 486

and term 7 = 486 x 3=1,458 and so on

Recall that nth term of GP is

Tn = ar^n-1

Where a= first term

r= common ratio

n= term

such that to easily find particular term, we plug in the values and calculate

for example the 10th term of the above sequence

Tn = ar^n-1

= 2 X 3 ^(10-1)

2 X 3^9

T10 =39,366

User JDur
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