Why is arc length of a function [tex]f(x)[/tex] from a to b defined as [tex]\int_a^b \sqrt{1+(f'(x))^2} dx[/tex]?(adsbygoogle = window.adsbygoogle || []).push({});

Where they get the idea of squaring the derivative, adding 1, taking the square root, and then integrating it is beyond me.

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# Arc Length Confusion

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