Determining the length of the curve (ln curve)

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Homework Statement



Determining the length of the curve (ln curve)
{ x = 1 + t + 1 / t
y = 3-2 lnt

between 1<= t <= 2

Homework Equations



Well Using the formula L = $ (from a to b) SQRT[x'(t)]^2 + [y'(t)]^2] dt

The Attempt at a Solution



I have a problem to go further from here, could someone help solve this?
 
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Using the formula you gave:

<br /> L=\int_{1}^{2}\left(1-\frac{1}{t^{2}}\right)^{2}+\left(-\frac{2}{t}\right)^{2}dt<br />

Expand and integrate...
 
hunt_mat:

I think you left out that the integrand in your expression for the arc length should be under a square root sign.
 
Your right, I have.
 
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