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The recursive rule for a sequence and one of the specific terms is given. Find the position of the giving term. f(1)= 8 1/2; f(n)= f(n-1) - 1/2; 5 1/2

The recursive rule for a sequence and one of the specific terms is given. Find the-example-1
User MontyGoldy
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1 Answer

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f(7) gives 5 1/2.

the position is the 7th term

Step-by-step explanation:

f(1)= 8 1/2

f(n)= f(n-1) - 1/2

we are looking for the function that gives 5 1/2

We have been given f(1), this means n = 1

f(1) = f(1-1) - 1/2

8 1/2 = f(0) - 1/2

f(0) = 8 1/2 + 1/2

f(0) = 8 + 1 = 9

when n = 2

f(2) = f(2-1) - 1/2

f(2) = f(1) - 1/2

f(2) = 8 1/2 - 1/2

f(2) = 8

when n = 3

f(3) = f(3-1) - 1/2

f(3) = f(2) - 1/2

f(3) = 8 - 1/2

f(3) = 7 1/2

when x = 4

f(4) = f(4-1) - 1/2

f(4) = f(3) - 1/2

f(4) = 7 1/2 - 1/2

f(4) = 7

when n = 5

f(5) = f(5-1) - 1/2

f(5) = f(4) - 1/2

f(5) = 7 - 1/2

f(5) = 6 1/2

f(6) = f(6-1) - 1/2

f(6) = f(5) - 1/2

f(6) = 6 1/2 - 1/2 = 6

when n = 7

f(7) = f(7-1) - 1/2

f(7) = f(6) - 1/2

f(7) = 6 -1/2 = 5 1/2

f(7) gives 5 1/2.

Hence, the position is the 7th term

User Jasper Lankhorst
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