calc help !! fan, testimonial , and medal!!!!
@iGreen
@phi i need serious help from like 2 days ago please!!
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: \[\frac{1}{8-0}\int_0^8W(t)\,dt\]
and i just plug in?
@Compassionate do you know??
@srossd ?
HI!!
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
\[\int \log(t^2+7)dt\] is not something i would want to compute without a calculator
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.
That first step was integration by parts, by the way.
3.0904 @srossd ?
what do you mean evaluate at 0 and 8?? @srossd
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.
thank you(:!!
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