Question 1165561
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<pre>

For any parametric curve in {{{R^3}}}

    p(t) = (x(t),y(t),z(t))


its length is the integral from "a" to "b" of


    {{{sqrt(((dx)/(dt))^2 + ((dy)/(dt))^2 + ((dz)/(dt))^2)}}}*dt.
</pre>


See, for example, this link


https://tutorial.math.lamar.edu/classes/calciii/vectorarclength.aspx