SOLUTION: If f(1)=9 and f(n)=-3f(n-1)+n then find the value of f(5)

Algebra.Com
Question 1198249: If f(1)=9 and f(n)=-3f(n-1)+n then find the value of f(5)
Found 2 solutions by ewatrrr, ikleyn:
Answer by ewatrrr(24785)   (Show Source): You can put this solution on YOUR website!

Hi  
f(n)=-3f(n-1)+ n
Given: f(1)= 9
f(2)=-3f(1)+ 2 = -25  Noted -3 coefficient
f(3) = -3f(2) + 3 = 75 + 3 = 78
f(4) = -3f(3) + 4 = -234 + 4 = -230
f(5) = -3f(4) + 5 = 690 + 5 = 695
Wish You the Best in your Studies.


Answer by ikleyn(52784)   (Show Source): You can put this solution on YOUR website!
.
If f(1)=9 and f(n)=-3f(n-1)+n then find the value of f(5)
~~~~~~~~~~~~~~


            Calculations made by @ewatrrr in her post all are incorrect.
            So I came to make it in a right way.
            Simply do it step by step. 


f(2) = -3f(1) + 2 = -3*9 + 2      =  -25

f(3) = -3f(2) + 3 = -3*(-25) + 3  =   78

f(4) = -3f(3) + 4 = -3*78 + 4     = -230

f(5) = -3f(4) + 5 = -3*(-230) + 5 =  695

Solved (correctly).

----------------

@ewatrrr re-wrote her post after seeing my calcs.




RELATED QUESTIONS

if f(1)=9 and f(n)=-3f(n-1)+n then what is the value of... (answered by ikleyn)
if f(1)=5 and f(n)=-3f(n-1) then... (answered by greenestamps)
If f(1)=9 and f(n)=f(n-1)+2 then find the value of... (answered by ikleyn,ewatrrr)
if f (1) = 6 and f (n)= f (n-1) + 2 then find the value of f... (answered by MathLover1)
If f(1) = 7 and f(n) = f(n - 1) + 2 then find the value of... (answered by ikleyn)
if f(1)=5 and f(n)=-2f(n-1)+2 then what is the value of... (answered by MathLover1)
If f(1)=3 and f(n)=−4f(n−1) then find the value of... (answered by ikleyn,MathLover1)
if f(1)=5 f(n)=4f(n-1)+1 then what is the value of f(3) (answered by MathLover1)
If f(1)=1, f(2)=2 and f(n)and =f(n−1)−f(n−2) then find the value of... (answered by greenestamps)