Posted by Jessica on Monday, February 25, 2008 at 3:52am.
They want you to do it two ways. The first is to change it to
dx/[2(1+x)] + dx/[2(1-x)]
which integrates to
(1/2)[ln(1+x) - ln(1-x)]
= (1/2)ln[(1+x)/(1-x)]
In the substitution method, with x = sin u
dx = cos u du
Integral dx/(1-x^2)= cos u du/1-sin^2u
= Integral du/cos u = Integral (sec u)
= (1/2)log[(1+sinu)/(1-sinu)]
= (1/2)log[(1+x)/(1-x)]
Related Questions
Calculus 2 - Evalute the integral of x/(x^2+4)dx using u-substitution and then ...
calculus - Integrate x/(x^2 + 4) dx via trig substitution and by u=x^2+4 ...
Calculus - I have two questions, because I'm preparing for a math test on ...
calculus - Assuming that: Definite Integral of e^(-x^2) dx over [0,infinity] = ...
calculus - We're doing indefinite integrals using the substitution rule ...
Calculus/Substitution - The integral from 1 to 2 of x*the square root of (x-1) ...
calc - find integral using table of integrals ) integral sin^4xdx this the ...
Calc - First make an appropriate substitution and then use integration by parts ...
calculus - Help with an integration question with the substitution given? Please...
Calculus - Integral of x sq/(1+x sq) dx I am not sure how to do this, am i ...
For Further Reading