Integral involving trig substitution

fran1942
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Hello, I am trying to integrate 1/(x^2-1).

Apparently this can be solved by using trig substitution involving tan ?
Can someone please help me to understand how to go about it.

Thanks kindly for any help.
 
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Let x= \sec \theta
 
Alternatively you can use partial fractions decomposition. You can also user ##x = \sin{(\theta)}## and multiply by (-1)/(-1).
 
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