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Homework Statement
Prove that any curve [itex]\Gamma[/itex] can be parameterized by arc length.
Homework Equations
Hint: If η is any parameterization (of [itex]\Gamma[/itex] I am guessing), let [itex]h(s) = \int^{s}_{a} \left| \eta ' (t) \right| dt[/itex] and consider [itex]\gamma = \eta \circ h^{-1}.[/itex]
The Attempt at a Solution
Given the hint, we have [itex]\gamma = \eta \circ h^{-1} (t) = (x(h^{-1} (t), y(h^{-1} (t))[/itex] and thus [itex] \left| \gamma ' (t) \right| = \sqrt{ [x' (h^{-1} (t))]^{2} + [y' (h^{-1} (t))]^{2}}[/itex] but what good is this if I can't find the inverse of h(t)?
I know I have to show there exists a parameterization [itex]\gamma : [a, b] \rightarrow \Re^{2}[/itex] of [itex]\Gamma[/itex] so that [itex]\left| \gamma ' (t) \right| = 1[/itex] for all t. Perhaps this hint will reveal this parameterization, but I can't see how. Any help would be appreciated.