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You are not logged in. #1 20130125 07:23:56
integrate x/sqrt(3x+25)In my homework for this week I have a question: If I do a substitution u=3x+25, then I have Which does not help much. If I try to find such u that du will eliminate x from numerator, then: du=1/x dx and u have to be ln(x) Which is also not very helpful... Finally I run the original integral through Maxima, and it gave me: Which is very scary and I have no idea how it come to this formula. So which "u" should I use? How to find such "u"? Or maybe there is another approach I should use? I am completely stuck. #2 20130125 07:42:10
Re: integrate x/sqrt(3x+25)Hi White_Owl Can you continue from here? Last edited by anonimnystefy (20130125 07:49:57) The limit operator is just an excuse for doing something you know you can't. “It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman “Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment #4 20130125 09:55:19
Re: integrate x/sqrt(3x+25)Hi White_Owl The limit operator is just an excuse for doing something you know you can't. “It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman “Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment #6 20130126 13:30:01
Re: integrate x/sqrt(3x+25)You're welcome! The limit operator is just an excuse for doing something you know you can't. “It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman “Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment 