How do you factor out dx in the arc length integral?

derek181 · Feb 22, 2014

I am just learning how to find lengths of curves using calculus. √((dx)²+(dy)²)→∫√(1+(dy)²)dx. My question is how are you able to bring out the dx. Is this some sort of algebraic trick I've never heard of. Can someone please explain this to me?

derek181 · Feb 22, 2014

nevermind, you just multiply by dx/dx

mathman · Feb 23, 2014

You should have √(1+(dy/dx)²) for the second integrand.

Boson · Mar 11, 2014

It is [{1+(dy/dx)^2}^0.5]dx = Length of curve

How do you factor out dx in the arc length integral?

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