Our function is

.
We want to find f(5).
Let's substitute 5 for n.
f(5) = -2f(5-1) + 1
f(5) = -2f(4) + 1
We need to know f(4).
f(4) = -2f(4-1) + 1
f(4) = -2f(3) + 1
We need to know f(3).
f(3) = -2f(3-1) + 1
f(3) = -2f(2) + 1
We need to know f(2).
f(2) = -2f(2-1) + 1
f(2) = -2f(1) + 1
We know that f(1) = 3
f(2) = -2(3) + 1
f(2) = -6 + 1
f(2) = -5
Now we can use f(2) = -5 to find f(3)...
f(3) = -2(-5) + 1
f(3) = 10 + 1
f(3) = 11
Now we can use f(3) = 11 to find f(4)...
f(4) = -2(11) + 1
f(4) = -22 + 1
f(4) = -21
Now we can use f(4) = -21 t find f(5)!
f(5) = -2(-21) + 1
f(5) = 42 + 1
f(5) = 43
Answer:
x = 5
y = 0
Step-by-step explanation:
3x + y = 15
3x -y = 15
Add the two equations;
6x = 30
Inverse operations;
6x = 30
/6 /6
x = 5
Back substitute;
3(5) + y = 15
15 + y = 15
y = 0
4x² - 16 is the algebraic expression that must be added to get the result as 9x²- 2x - 5.
<u>Step-by-step explanation:</u>
The question is asked for the algebraic expression must be added to the sum of 3x²+4x+8 and 2x2−6x+3 to give 9x²- 2x - 5 as the result.
Therefore,
The first step is to find of sum of 3x²+4x+8 and 2x²-6x+3.
To find the sum :
3x²+4x+8
<u>2x²-6x+3 </u>
<u>5x²-2x+11</u>
The sum is 5x²-2x+11.
Now, the second step is to subtract 5x²-2x+11 from the result 9x²- 2x - 5.
9x²- 2x - 5
- <u>(5x²-2x+11)</u>
<u> 4x² -16 </u>
Thus, 4x²-16 is the algebraic expression that must be added with 5x²-2x+11 to get a result of 9x²- 2x - 5.