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DIfferential equation help

8 Answers
If t=integration of [(100pai)dh/(5- sqrt(h))]find time, in seconds by means of substitution x=sqrt(h)-5 given that h=depth of water, sqrt is square root btw. find t for a definite integral he=121 and h=100
A

No the correct answer is t = 1201.09,

If x = h^1/2 - 5, then dx = [(1/2)h^-1/2]dh, or dh = 2dx(x+5).

The integral INT{[100pi/(5-h^1/2)]dx becomes -(200pi)Int{[(5/x)+1]dx} with limits 6 to 5.

The result is t = -200pi[5lnx + x] with those limits. Substituting in the limits one gets

t = 200pi[5ln6/5 + 1] = 1201.09.

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A

are you using a Word (or similar) program, then scanning in the results in order to be able to use more advanced symbols? It is really annoying that Mybestanswer is so technologically retarded.

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F

Here is how I completed the integration.

I did not post this earlier since I did not know whether you were being graded on this work.

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L

According to my calculations, the result I got is 1201,0986 and I have used the trapezoidal rule in order to calculated it.

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F

I agree with Lifell69 and Angels55

This is how I set up the integral.

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F

Just to clarify, are you asking us to solve the following problem?

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V

Too bad. The answer is t=11600 seconds. Or is the answer wrong?

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V

Yes pls help :)

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