Question

The following function defines a recursive sequence:

f(0) = -2

f(1) = 8

f(n) = -4•f(n -1) - 3•f(n - 2); for n > 1

Which of the following sequences is defined by this recursive function?

A. -2, 8, -26, -80, …

B. -2, 8, -26, 80, …

C. -2, 12, -44, 180, …

D. -2, -12, -44, -180, …

Answer 1

Well, the ones that don't have f(1) = 8 seem to be poor candidates.

Answer 2

yeah

Answer 3

Calculate f(2) = -4•f(1) - 3•f(0)

Answer 4

uhm... yeah i don't know how to do that

Answer 5

Yes you do.

What is f(0)?
What is f(1)?

Answer 6

oh -2 and 8 sorry went blank

Answer 7

f(2) = -4•8 - 3•(-2) = ??

Answer 8

-26?

Answer 9

Okay. Now is the time to make a final decision.

Find f(3) = -4•f(2) - 3•f(1)

Answer 10

A?

Answer 11

B!!!!! yay!!

Answer 12

I realize this is what you just helped with but it looks more confusing.

The first four terms of a sequence are shown below:

7, 4, 1, -2
3 and -3??
Which of the following functions best defines this sequence?

f(1) = 7, f(n + 1) = f(n) + 3; for n ≥ 1

f(1) = 7, f(n + 1) = f(n) - 3; for n ≥ 1

f(1) = 7, f(n + 1) = f(n) - 4; for n ≥ 1

f(1) = 7, f(n + 1) = f(n) + 4; for n ≥ 1

Answer 13

What does this mean "3 and -3??"

7-4 = 3
4-1 = 3
1-(-2) = 3

I'm seeing a pattern.

Answer 14

7 - 4 = 3
i did math wrong for 1,-2

Answer 15

subtracting 3?

Answer 16

so basically its the second answer lol that didn't take long

Answer 17

That's all there is to it. :-)

Answer 18

Since youre here and seem pretty good with math can you help me with my final exams?

Answer 19

You're funny. Have to do exams on your own. Do well, though.

Answer 20

aha thanks. Hopefully. thanks for your help!! ^_^