(a) The "average value" of a function over an interval [a,b] is defined to be
(1/(b-a)) times the integral of f from the limits x= a to x = b.
Now S = 200(5 - 9/(2+t))
The average value of S during the first year (from t = 0 months to t = 12 months) is then:
(1/12) times the integral of 200(5 - 9/(2+t)) from t = 0 to t = 12
or 200/12 times the integral of (5 - 9/(2+t)) from t= 0 to t = 12
This equals 200/12 * (5t -9ln(2+t))
Evaluating this with the limits t= 0 to t = 12 gives:
708.113 units., which is the average value of S(t) during the first year.
(b). We need to find S'(t), and then equate this with the average value.
Now S'(t) = 1800/(t+2)^2
So you're left with solving 1800/(t+2)^2 = 708.113
<span>I'll leave that to you</span>
Answer:
3200 ft-lb
Step-by-step explanation:
To answer this question, we need to find the force applied by the rope on the bucket at time 
At 
After seconds, the weight of the bucket is 
Since the acceleration of the bucket is the force on the bucket by the rope is equal to the weight of the bucket.
If the upward direction is positive, the displacement after seconds is 
Since the well is 80 ft deep, the time to pull out the bucket is 
We are now ready to calculate the work done by the rope on the bucket.
Since the displacement and the force are in the same direction, we can write
Use and 
![=\left[63 t-0.2 t^{2}\right]_{0}^{36}](https://tex.z-dn.net/?f=%3D%5Cleft%5B63%20t-0.2%20t%5E%7B2%7D%5Cright%5D_%7B0%7D%5E%7B36%7D)
Answer:
Step-by-step explanation:
Let c represent the number of children that attended the concert.
Let a represent the number of adults that attended the concert.
At one of the concerts, each adult brought 4 children with them, and 10 children attended without an adult. This means that the number of children that attended is
c = 4a + 10
Tickets for a concert were $5 for each child and $8 for each adult. The total ticket sales were $1730. It means that
5c + 8a = 1730
Therefore, the systems of equations that can be solved to determine the number of children, c, and adults that attended the concert is
c = 4a + 10
5c + 8a = 1730
I would use the equation
24 + 8x = 112
let x = the amount of CDs she bought.
Hope this helps!!
Answer:
min = 64.2m ; max = 86.2m
Step-by-step explanation:
