Hey guys,(adsbygoogle = window.adsbygoogle || []).push({});

Got a bit of a problem with a question I found in a text book. I can do most of it but theres one little part I'm really struggling with:

A curve C is given parametrically by:

x=t-tanht, y=secht, t[tex]\geq0[/tex]

The length of arc C measured from the point (0,1) to a general point with parameter t is s. Find s in terms of t and deduce that, for any point on the curve, y=e^{-s}.

I'm happy finding that the arc length is defined as [tex]\int (tanht)dt[/tex] between the limits of 0 and s, and i evaluate this integral to be ln(coshs) however after this I am stumped; I am having great trouble getting to y=e^{-s}.

Can anyone please help me out?

Oscar

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# Arc Length Problem

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