Question

The following function defines a recursive sequence:

f(0) = -3

f(1) = 6

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

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

-3, 6, -9, -12, …

-3, 20, -95, 480, …

-3, 6, -9, 12, …

-3, -20, -95, -480, …

Answer 1

try to find f(2)
replace all n's with 2 and tell me what you get after doing only that step

Answer 2

ok

Answer 3

so in f(n) put 2 inplace of n i.e.,n=2
and match the 3rd term and so on.

Answer 4

have you replaced all the n's with 2's in the recursive function:
f(n)=-2*f(n-1)-f(n-2) ?

Answer 5

I'm almost done @myininaya

Answer 6

ok. f(2)=-2f(2-1)-f(2-2)
=-2f(1)-f(0)
=-2*6-(-3)
=-12+3=-9

Answer 7

how did you get 6 @neer2890

Answer 8

f(1)=6 and f(0)=-3
it's given in question

Answer 9

ok

Answer 10

in the same way now find f(3) to find the exact answer.

Answer 11

so the answer is either a or c

Answer 12

yeah..so to find the correct answer you have to find f(3) by placing 3 inplace of n in f(n)

Answer 13

ok

Answer 14

@neer2890 i got c

Answer 15

dang... you're correct...good

Answer 16

thanks :)

Answer 17

anytime...:)