Derivative using Logarithmic Differentiation

marc_2094
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Homework Statement



http://www.flickr.com/photos/50468243@N02/8577233960/

Homework Equations





The Attempt at a Solution



In the pic, the noticeable difference between my answer and Wolframalpha's is the tan[log(sin x+1) to base 5]. If I do logarithmic differentiation, what I get is my Answer (the one in the pic) but when I do product rule (I get the same answer with Wolframalpha). Please help. I'm confused. THanks! :)
 
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You're not doing the logarithmic differentiation correctly.
 
Can you please help me find out what I did wrong?
 
marc_2094 said:
Can you please help me find out what I did wrong?

In order to do so, you will need to write out here all the steps you took to get from the problem to your answer. It would be better if you typed the steps out using LaTeX.
 
I'll admit I didn't check your answers. It could be you're doing the product rule incorrectly. (I simply sided with Wolfram Alpha, but you may have messed up using it as well.) In any case, we can't tell where you're going wrong if all you do is post your final results. Doing so is like saying, "My car won't start. What's wrong?"
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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