Ask your own question, for FREE!
Mathematics 10 Online
OpenStudy (wade123):

calc help !! fan, testimonial , and medal!!!!

OpenStudy (anonymous):

@iGreen

OpenStudy (wade123):

@phi i need serious help from like 2 days ago please!!

OpenStudy (anonymous):

Since \(R(t)\approx W(t)\) gives the rate of the water flow, the average rate of flow is given by the average value of \(W(t)\). This amounts to settig up and evaluating the following integral: \[\frac{1}{8-0}\int_0^8W(t)\,dt\]

OpenStudy (wade123):

and i just plug in?

OpenStudy (wade123):

@Compassionate do you know??

OpenStudy (wade123):

@srossd ?

OpenStudy (misty1212):

HI!!

OpenStudy (misty1212):

assuming @sithsandgiggles is right, here is your answer http://www.wolframalpha.com/input/?i=%28int+0+to+8++ln%28x^2%2B7%29%29%2F8

OpenStudy (misty1212):

\[\int \log(t^2+7)dt\] is not something i would want to compute without a calculator

OpenStudy (anonymous):

Yes, you plug in W(t). So it becomes \[\frac{1}{8}\int\limits_0^8 \ln(t^2+7)\,dt\] Now, you need the antiderivative. This isn't fun. Here goes: \[\int \ln(t^2+7)\,dt = t\ln(t^2+7)-\int \frac{2t^2}{t^2+7}\,dt \\ = t\ln(t^2+7)-2\int 1- \frac{7}{t^2+7}\,dt = t\ln(t^2+7)-2t + 2\sqrt{7}\tan^{-1}(t/\sqrt{7})\] Then you can evalulate that at 0 and 8 and subtract.

OpenStudy (anonymous):

That first step was integration by parts, by the way.

OpenStudy (wade123):

3.0904 @srossd ?

OpenStudy (wade123):

what do you mean evaluate at 0 and 8?? @srossd

OpenStudy (anonymous):

Yes, 3.0904 is correct. You take the antiderivative, plug in t = 0, subtract that from the value at t =8, and then divide by 8 to get the average.

OpenStudy (wade123):

thank you(:!!

Can't find your answer? Make a FREE account and ask your own questions, OR help others and earn volunteer hours!

Join our real-time social learning platform and learn together with your friends!
Can't find your answer? Make a FREE account and ask your own questions, OR help others and earn volunteer hours!

Join our real-time social learning platform and learn together with your friends!