How to integrate sqrt((ax+b)/x) dx (square root of linear fractional function)

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To integrate sqrt((ax+b)/x) dx, the substitution u = (ax+b)/x is suggested to simplify the expression. Another approach involves letting v = sqrt(u) and using the relationship v^2 = u to facilitate integration. The discussion emphasizes that this method may lead to a more manageable integral. Additionally, a specific substitution x = (b/a)(sinh(t))² is proposed for further simplification. Resources like Wolfram Alpha are recommended for additional assistance in solving the integral.
Holali
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Hi,
simple question, but difficult to find an answer for me

How to integrate sqrt((ax+b)/x) dx ?
a,b constants and x variable

if it matters, I would be happy if you could solve it just for both a,b >0

Thanks
 
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Let u=\frac{ax+b}{x}. We're keeping our fingers crossed, there's no other common methods that apply, so this looked like most natural thing to do.

The expression will be a little simpler, but now we try a more common method, which is let v=\sqrt{u}. To find du, we usually consider v^2=u, to simplify things. I think you will end up with something that you know how to integrate.
 
Holali said:
Hi,
simple question, but difficult to find an answer for me

How to integrate sqrt((ax+b)/x) dx ?
a,b constants and x variable

if it matters, I would be happy if you could solve it just for both a,b >0

Thanks

Let x = (b/a)(sinh(t))²
 
go here:


integrals.wolfram.com/index.jsp

and enter

sqrt[(a*x+b)/x]

into the text box
 

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