Path integral (scalar line integral) from vector calculus

Free ebook http://tinyurl.com/EngMathYT
I discuss and solve an example involving a path integral (also known as a scalar line integral) from vector calculus. In particular, I integrate a given function over a helix in 3D-space, where the integration is with respect to arc length. Such concepts are seen in 2nd-year university mathematics and enjoy applications to engineering.