Answer:
7/9 son azules. hay 27 en total y hay 6 lapices de blanco
Step-by-step explanation:
Answer:
cos 330
Step-by-step explanation:
Morse code is essentially the same as binary. That is, there are two "digits", a dot or a dash.
There are 26 letters in the English alphabet. Clearly, we can't just use one dot or dash, since that could only encode 2 letters at the most. We can't use two symbols because that could only encode 4 letters at the most. Similarly, 3 symbols means
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letters at most.
We have to select the smallest power of 2 that exceeds or is equal to 26. In this case,
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, so we would have to use up to 5 symbols to encode each letter in the alphabet.
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).