How Do You Calculate Arc Length in Polar Coordinates for r = e^θ?

Mk_
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Homework Statement


r = e^θ
find arc length from (1,0) to origin


Homework Equations


∫ab sqrt (r^2 + (dr/dθ)^2) dθ


The Attempt at a Solution


∫10 sqrt ((e^θ)^2 + (e^θ)^2) dθ

∫10 sqrt (2(e^θ)^2) dθ

∫10 sqrt (2) (e^θ) dθ

sqrt (2) ∫10 (e^θ) dθ

need help converting limits in terms of theta
 
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For what value of theta is e^\theta equal to zero?
 
Mk_,
uart's question is a bit of a trick question, since eθ is always positive for any finite number θ.
 
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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