I see how that integral becomes 1-1/(x^2+1)
I see I have to use trig ...I draw some pictures and I don't get it
how do you take integral of 1/(x^2+1)
help...
I see how that integral becomes 1-1/(x^2+1)
I see I have to use trig ...I draw some pictures and I don't get it
how do you take integral of 1/(x^2+1)
help...
Let x = tan(theta)
Then dx = sec^2(theta) d(theta)
x^2 + 1 = tan^2(theta) + 1 = sec^2(theta)
So dx/(x^2 + 1) = sec^2(theta) d(theta)/sec^2(theta) = d(theta)
Don't forget to change the limits! (I always do anyway. )
It is a tabular integral you need to have it burned in your memory.
It is the arctangent function.
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That is exactly what I would have done topsquark.