Splitting Fractions (Integrals)

FuturEngineer
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Homework Statement


Evaluate

Integrate (2-3x/(Sqrt.(1 - x^2))) dx

Homework Equations


1/Sqrt.(1-x^2) = arctan

The Attempt at a Solution


I am so lost, but this is what I've tried, but didn't work...

I separated the integral into two so
Integral of (2/(Sqrt.(1-x^20))) dx - integral of (3x/(Sqrt.(1-x^2))) dx
I am not sure how to proceed? Help! [/B]
 
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this can be solved using a trig substitution for x. Can you think of what this substitution should be to simplify the denominator?
 
FuturEngineer said:

Homework Statement


Evaluate

Integrate (2-3x/(Sqrt.(1 - x^2))) dx

Homework Equations


1/Sqrt.(1-x^2) = arctan

The Attempt at a Solution


I am so lost, but this is what I've tried, but didn't work...

I separated the integral into two so
Integral of (2/(Sqrt.(1-x^20))) dx - integral of (3x/(Sqrt.(1-x^2))) dx
I am not sure how to proceed? Help! [/B]
Looks like a natural for trig substitutions for both integrals
 
I would NOT use a trig substitution for \frac{3x}{\sqrt{1- x^2}}. Instead let u= 1- x^2
 
HallsofIvy said:
I would NOT use a trig substitution for \frac{3x}{\sqrt{1- x^2}}. Instead let u= 1- x^2
A trig substitution would work, but I agree that an ordinary substitution (as you suggest) would be easier, which makes it a better choice.
 
Thanks!
 
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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