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anonymous
 5 years ago
Differentiate the given function:
f(x)= ln (x+1)/(x1)
I get 2/(x1)^2
anonymous
 5 years ago
Differentiate the given function: f(x)= ln (x+1)/(x1) I get 2/(x1)^2

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anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I used the quotient rule, but not sure what to do with the ln

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0did u have? ln(x+1/x1)?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0if yes, then d/dx (lnx)= 1/x ... easy

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0the ln is before the fraction

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Quotient rule u= ln (x+1) v= ln (x1)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0If ln is over the whole thing ln [(x+1)/(x1)] rewrite as [ln (x+1)]/[ln (x1)]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I don't know if this will help ln x+1 x1 x+1/x1 one big parenthesis around this fraction

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Can be rewritten as \[\ln (x+1)\div \ln (x1)\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I have not done it that way

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0what shorthand you use for quotient rule f(x) or what?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0ok for quotient rule, I can do that but not sure what to do with the ln. After the quotient rule I get (x1)(x+1) / (x1)^2

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Excuse me for using u and v. Let u=ln (x+1), let v=ln (x1) u'=?, v'=? u' means u prime or derivative of u The derivative of the whole thing is \[(u'vuv')\div(v ^{2})\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I am sorry but I am having a real hard time understanding this math. I have a book that has this problem worked out. I just don't understand why certain things are done the way they are. The last section we went over was dervatives and I did really well with them. These I am not.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0OK, so write one or two steps from book and say what you don't understand

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.01st step f'(x) = 1/(x+1/x1) d/dx (x+1/x1) why did they put 1 over the problem.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0next step x1/x+1 [(x1)(1)  (x+1)(1)//(x1)^2 the 2nd half I get, that is the quotient rule

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0they are treating the whole fraction thingy as a single number. Let (x+1)/(x1) be u (sorry) f' of ln u=1/u

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Deal with one question at a time or everything would get confused

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0ok with step one 1/(x+1/x1) then I guess they took the bottom # and flipped and multiplied. Is that how the problem got switched for step 2

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0OK, back to original question what might make it a little confusing is what is called chain rule. the f' (x) = 1/[x+1/(x1)] du in addition to this you must find the derivative of the inner function (x+1)/(x1). Find the derivative of that and that is your du. This is a complicated function. I can explain more after you look at it.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0why can't I use the quotient rule

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0by putting the 1 / .... is that taking the ln out of the problem

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0There is a lot going on in this problem. It is not that you can't use quotient rule. In fact they are using quotient rule. But there are some intricacies that make their answer difficult to understand. Start from the top. Ask one piece by one piece what you don't understand.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0ok 1st step 1/ (x+1/x1) if I use the quotient rule derv. is x+1/x1

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0never mind that isn't correct.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Just write the book line by line and I will do the play by play

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.01st step f'(x) = 1/(x+1/x1) d/dx (x+1/x1) 2nd step x1/x+1 [(x1)(1)  (x+1)(1)/(x1)^2 step 3 2/(x+1)(x1) That is all steps

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Are you familiar with the thing called the chain rule?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0There approach is good. Now that I see it. They considered the ln (that thing) ln (that thing)=[1/(that thing)][multiplied by derivative of that thing] They didn't find it necessary to do the quotient rule to find f'(x), but in finding the derivative of (that thing) they did the quotient rule. Derivative of ln doesn't require work, you just put 1/something

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0ok I half way understand that but how did they get x1/x+1 in step 2 before the quotient rule

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0sometimes when they work the problems out in the book it doesn't explain what they are doing. If I understand the work it does not confuss me.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0You have fractional property at the bottom is flipped.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0ok you flip it to get rid of the 1

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0ok on step 2 x1/x+1 [(x1)(1)(x+1)(1)/(x1)^2 ok I can see the quotient rule what are they doine with the x1/x+1, are they multipling that by the quotient?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0never mind something just clicked, I see it now. They cross multiplied
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