Answer:
f) a[n] = -(-2)^n +2^n
g) a[n] = (1/2)((-2)^-n +2^-n)
Step-by-step explanation:
Both of these problems are solved in the same way. The characteristic equation comes from ...
a[n] -k²·a[n-2] = 0
Using a[n] = r^n, we have ...
r^n -k²r^(n-2) = 0
r^(n-2)(r² -k²) = 0
r² -k² = 0
r = ±k
a[n] = p·(-k)^n +q·k^n . . . . . . for some constants p and q
We find p and q from the initial conditions.
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f) k² = 4, so k = 2.
a[0] = 0 = p + q
a[1] = 4 = -2p +2q
Dividing the second equation by 2 and adding the first, we have ...
2 = 2q
q = 1
p = -1
The solution is a[n] = -(-2)^n +2^n.
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g) k² = 1/4, so k = 1/2.
a[0] = 1 = p + q
a[1] = 0 = -p/2 +q/2
Multiplying the first equation by 1/2 and adding the second, we get ...
1/2 = q
p = 1 -q = 1/2
Using k = 2^-1, we can write the solution as follows.
The solution is a[n] = (1/2)((-2)^-n +2^-n).
Answer:
4 parts
Step-by-step explanation:
If the total number of parts is 12 and you want to reduce the dish to two-thirds its current size, the number of parts that will be reduced is (1 - 2/3) = 1/3
To reduce 1/3 of the 12 parts, you need to multiply 12 by 1/3 to know how many parts is that:
12 * 1/3 = 12/3 = 4
You need to subtract 4 parts. If you have 4 ingredients, you can remove 1 part of each, so each ingredient now will have 2 parts.
<u>exact form:</u>
w= 74/45
<u>decimal form:</u>
w= 1.64
<u>mixed number:</u>
w= 1 29/45
brainliest would be appreciated :)
The three numbers are 52, 53, 54.
52+53=105 105+54=159
Answer:
72
Step-by-step explanation:
