Answer:
a) -7/9
b) 16 / (n² + 15n + 56)
c) 1
Step-by-step explanation:
When n = 1, there is only one term in the series, so a₁ = s₁.
a₁ = (1 − 8) / (1 + 8)
a₁ = -7/9
The sum of the first n terms is equal to the sum of the first n−1 terms plus the nth term.
sₙ = sₙ₋₁ + aₙ
(n − 8) / (n + 8) = (n − 1 − 8) / (n − 1 + 8) + aₙ
(n − 8) / (n + 8) = (n − 9) / (n + 7) + aₙ
aₙ = (n − 8) / (n + 8) − (n − 9) / (n + 7)
If you wish, you can simplify by finding the common denominator.
aₙ = [(n − 8) (n + 7) − (n − 9) (n + 8)] / [(n + 8) (n + 7)]
aₙ = [n² − n − 56 − (n² − n − 72)] / (n² + 15n + 56)
aₙ = 16 / (n² + 15n + 56)
The infinite sum is:
∑₁°° aₙ = lim(n→∞) sₙ
∑₁°° aₙ = lim(n→∞) (n − 8) / (n + 8)
∑₁°° aₙ = 1
Answer:
34
Step-by-step explanation:
Hello!
To do this we need to combine like terms, meaning combine the terms that have the same variables.
b is one variable that can be combined:
-2b - 6 + 3b - 2
b - 6 - 2
Now, combine the digits:
b - 8
Hope this helped!
It would be nice to know some options, but here's Morris's speed.
Since Morris is traveling at three feet per second, we want to change it to per hour.
3 * 3600 = 10800 feet per hour
And we would want to convert that to miles per hour.
10800/5280 is about 2, more specifically 2.05 ish.
So Morris is traveling 2 mph less then 50, or about 48 mph.
Answer:
the answer for number 4 is c
