Find d/dx of hyperbolic function

silicon_hobo
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[SOLVED] find d/dx of hyperbolic function

Homework Statement


Find:
http://www.mcp-server.com/~lush/shillmud/1.1A.Q.JPG

Homework Equations


d/dx f(x)*g(x) = f(x) * d/dx g(x) + g(x) * d/dx f(x)
d/dx f(g(x)) = d/dx f(g(x))* d/dx g(x)
d/dx sinh x = cosh x
d/dx cosh x = sinh x

The Attempt at a Solution


http://www.mcp-server.com/~lush/shillmud/1.1A.A.JPG

Can this be further simplified? When I run it in maple I get:
http://www.mcp-server.com/~lush/shillmud/1.1A.C.JPG

I'm probably going to be posting here often so let me give you a little background. I am beginning calc II by correspondence. It is the last course of my undergrad and I haven't done any pure math courses in a while. I think things are going alright so far but without a prof or fellow students I sometimes become stuck or find it difficult to check an answer in a way that allows me to move on to the next question with confidence. I thought maple might help me check my answers but in this case it's left me more confused. Thanks for reading!

P.S. How do I use special math characters (like infinite etc.) in my post as have seen some people do?
 
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What you have is perfectly correct. I can't speak for the Maple (especially not if they include "ln(e)" in the answer!
 
I expect it's simply a matter of applying a (hyperbolic) trig identity to show they are equal.

Plugging in 5 or 6 (non-special!) values of x should, at least, give you high confidence that those expressions are, in fact, equal.
 
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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