Improper integral concept help.

frasifrasi
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Ok, my book has the example int from -1 to 2 of dx/x^3

this gets split into int from -1 to 0 of dx/x^3 and int from 0 to 2 of dx/x^3.

Now, he had previously determined that the second integral returned positive infinity (diverges) by taking the lim as b approaches 0+.


So, the book goes on to say that since the second integral diverges the original integral also diverges.

--> but what does that mean? is "divergers" the answer to "evaluate the int from -1 to 2 of dx/x^3" ? Or does it mean the the answer is just infinity?

Can anyone explain?
 
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It means that it diverges.
 
so what is the answer ? what does this mean ?? what should I conclude from this? does it mean that I shoudl stope evaluating the original improper integral?

I would appreciate HELPFUL input. If you aren't going to clarify the solution, please igonre the thread.
 
frasifrasi said:
so what is the answer ?
There is none.
what does this mean ?? what should I conclude from this?
That the expression is meaningless.
does it mean that I shoudl stope evaluating the original improper integral?
Quite so.
 
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