Can This Integral Be Solved Using Factoring and Substitution?

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whatlifeforme
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Homework Statement


evaluate the integral.

Homework Equations


[itex]\displaystyle\int {\frac{3x+2}{\sqrt{1-x^2}} dx}[/itex]

The Attempt at a Solution


- i tried factoring hoping for a perfect square that i could take the square root of, but that doesn't work.

-u-sub won't work: u=1-[itex]x^2[/itex] ; du=2x

-i don't know how to use that denominator in partial fractions.
 
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whatlifeforme said:

Homework Statement


evaluate the integral.

Homework Equations


[itex]\displaystyle\int {\frac{3x+2}{\sqrt{1-x^2}} dx}[/itex]

The Attempt at a Solution


- i tried factoring hoping for a perfect square that i could take the square root of, but that doesn't work.

-u-sub won't work: u=1-[itex]x^2[/itex] ; du=2x

Break it up into two:##\int\frac{3x}{\sqrt{1-x^2}}dx + \int\frac{2}{\sqrt{1-x^2}}dx##.

Observe that ##3x = -\frac{3}{2}*(-2x)##, and now you should be able to make an obvious sub to resolve the first integral.

For the second integral, just make a simple trig sub.

Partial fractions wouldn't work here because of that square root in the denominator.