Question

Please help? I don't understand, will give medal.
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?

A. -3, 6, -9, -12, …

B. -3, 20, -95, 480, …

C. -3, 6, -9, 12, …

D. -3, -20, -95, -480, …

I believe it is either A, or C.

Answer 1

\[f(n) = -2f(n -1) - f(n - 2)\]

Answer 2

this means the next term is two times the previous term minus the term before that

Answer 3

ok,
f(0) = -3 , first term = -3

f(1) = 6, 2nd term = 6
so, as of now our sequence is -3,6

to find nect term, we will use
f(n) = -2•f(n -1) - f(n - 2)

put n= 2 here, what do u get ?

Answer 4

you just replace "n" by "2" there,
to get f(2)

Answer 5

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

and you already know
f(1) =6, f(0) = -3
just plug in values!

Answer 6

you need to find f(3) too!
f(3) = - 2f(2) - f(1) = - 2(-9) -6 = 18-6 = 12

Answer 7

oops
\[f(2)=-2f(1)-f(0)=-2\times 6-(-3)\]

Answer 8

So then it would be C ?

Answer 9

yes

Answer 10

yeah it is always C

Answer 11

Thank you so much! Both of you, wish I could give you both medals :/

Answer 12

who help you the most is the one you should give a medal too

Answer 13

if you felt @satellite73 help u the most give it to satellite

Answer 14

lol i have plenty, no worries

Answer 15

okay lol

Answer 16

plus @lupita1995 is most helpful here

Answer 17

awwwwwwwwwwwwwwwww

Answer 18

thank you