(f+g)(3) = f(3) + g(3) = 6(3) + 3 + 3 -7 = 18 +6 -7 = 17.
Answer: 17
The wording of this question is a bit confusing... You can't write a sequence in sigma notation, but rather a series or sum. I think the question is asking you to write the sum of the sequence,

which would be

in sigma notation.
To do this, notice that the denominator in each term is a power of 2, starting with
and ending with
. So in sigma notation, this series is

Answer:
x = 2 and y = 3
Step-by-step explanation:
We have
x+2y = 8 -----equation (i)
2x-y = 1 -----equation (ii)
Now,
x+2y = 8
or, x = 8-2y ------equation (iii)
Again,
2x-y = 1
or, 2x = 1+y
or, 2x-1 = y
Putting the value of 'x' from equation (iii)
or, 2(8-2y)-1 = y
or, 16-4y-1 = y
or, 16-1 = y+4y
or, 15 = 5y
or, y = 15/5
or, y = 3
Putting the value of 'y' in equation (iii)
x = 8-2y
or, x = 8-(2×3)
or, x = 8-6
or, x = 2
Therefore, x = 2 and y = 3.
Answer:
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