How to Simplify the Solution of a Definitive Integral?

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Any ideas how to solve this
\int_0^h {\frac{1}{\sqrt{1+(r({\frac{1}{z}}-{\frac{1}{h}}))^2}}}\,dz
Don't have an idea from where to begin
 
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The correct term is 'definite integral'.

Is r a constant?
 
Yeah, this is problem from ED R is radius and h is height of cone.
 
Djokara said:
Any ideas how to solve this
\int_0^h {\frac{1}{\sqrt{1+(r({\frac{1}{z}}-{\frac{1}{h}}))^2}}}\,dz
Don't have an idea from where to begin

Start by simplifying the integrand.
 
Djokara said:
Any ideas how to solve this
\int_0^h {\frac{1}{\sqrt{1+(r({\frac{1}{z}}-{\frac{1}{h}}))^2}}}\,dz
Don't have an idea from where to begin

How about this: We have the expression:

\frac{1}{\sqrt{1+(r/z-a)^2}}

now, can you simplify that and get:

\frac{z}{\sqrt{Q(z)}}

where Q(z) is a quadratic polynomial in z? Then we'd have:

\int \frac{z}{\sqrt{Q(z)}} dz

Now I don't know about you, but I'd look in my Calculus textbook about integrands with radicals with quadratic expressions (I did). And what is the first thing done when that happens?
 
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That worked but solution is messy.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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