Question

The first four terms of a sequence are shown below:
8, 5, 2, -1

Which of the following functions best defines this sequence? (4 points)


f(1) = 8, f(n + 1) = f(n) + 3; for n ≥ 1
f(1) = 8, f(n + 1) = f(n) - 5; for n ≥ 1
f(1) = 8, f(n + 1) = f(n) + 5; for n ≥ 1
f(1) = 8, f(n + 1) = f(n) - 3; for n ≥ 1

Answer 1

can you tell me what f(1) is.

Answer 2

I don't know

Answer 3

in other words first number of sequence

Answer 4

look at first number of your numbers group. and tell me first number

Answer 5

8

Answer 6

yes. that is f(1)
so f(1) = 8

Answer 7

now tell me second number, it will be f(2)

Answer 8

I don't know?

Answer 9

f(2) = 5

Answer 10

get it?

Answer 11

I guess

Answer 12

mm.. okay.
can you see there is a relationship you can tell

5 = 8 -3
f(2) = f(1) -3

Answer 13

Yes but what does it have to do with the equation

Answer 14

yes. so it works everywhere

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

and you can say a common equation instead of saying every equation above,

f(n+1) = f(n) -3

Answer 15

Okay, so what would the answer be ?..

Answer 16

well it is last one.