Let L R2 be a line through the origin, and let b 6 R2 be any point. (a) Find a geometrical construction of the

Let L Š‚ R2 be a line through the origin, and let b 6 R2 be any point.
(a) Find a geometrical construction of the closest point x e L to b when distance is measured in the standard Euclidean norm.
(b) Use your construction to prove that there is one and only one closest point.
(c) Show that if 0 ‰  a ˆˆ L, then the distance equals

using the two-dimensional cross product (3.22).

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