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Can some one intergrate 2*((r^

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zsmith

Structural
Aug 25, 2003
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Can some one intergrate

2*((r^2-x^2)^0.5)dr from (r-c) to r

where r is defined as 7
but c is undefined

thus you get an expression for 'c' that I can substitute
into another equation and then solve for 'c'

This should be the small area of a circle divide my a chord length

Thanks
 
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You might want to work on your notation a bit.

It does not make sense in my opinion - what is x? why does r appear in the limits, and in the formula, and as the integrating variable?

However on the assumption you are correct

the indefinite integral comes to

r*sqrt(r^2-x^2)-x^2*ln(r+sqrt(r^2-x^2))+A

where A is a constant

But as I said, probably meaningless



Cheers

Greg Locock
 
I believe the intended intral is:

integral(a,b, sqrt(R^2 - x^2),dx)
then MathCAD can symbollically
evaluate this integral. Also note
that the limits are:

a = C (Not R - C),

and

b = R (radius of the circle)

Incidentally, C <= R.

You may want to consider changing the lower
limit to C a percentage of radius !!

Take care,

The Mathemagician !
 
integral of 2*(r^2-x^2)^0.5 dr is:
(r-c)*((r-c)^2-x^2)^0.5
-x^2*ln(r-c+((-x+r-c)*(r-c+x))^0.5)
- r*(r^2-x^2)^0.5
+x^2*ln(r+((-x+r)*(r+x))^0.5)


Hope this helps
 
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