Solving Int. with Trig Substitution for Beginners

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stihl29
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Homework Statement


[tex]\int\frac{\sqrt{1+x}+\sqrt{1-x}} { \sqrt{1+x}-\sqrt{1-x}}{dx}[/tex]


Homework Equations


I believe trig substitution can be used here. I'm not very good at calculus only beginning to take calc classes, and guideance would be wonderful. because i want to get better.


The Attempt at a Solution


I don't have any idea on what to substitute.
x = some thing like x^2 ??
or u = 1 - x
and u = 1 + x ??
 
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The first thing you want to do is simplify the expression algebraically. It will help to rationalize the denominator by multiplying numerator and denominator by sqrt(1-x)+sqrt(1+x). The trick here is that (sqrt(a)-sqrt(b))*(sqrt(a)+sqrt(b))=a-b. Try simplifying it and see how far you can get.
 
ohhhh, thank you, i can't attempt it at this moment but your solution looks promising !