The FOURTH of the seven beauties. The integral of the position vector dotted the curvature normal.

[@statebased]

Thanks for this series of math happiness! When math is used professionally, we are rarely allowed to express our joy of these little properties that we may be using. Yet deep down, that is why we do math, for these pleasures.

[@ktuluflux]

Omg the product rule and integration by parts is the same thing

[@Pluralist]