Let x + y + 3 z = 7 represent a plane. (it does)(adsbygoogle = window.adsbygoogle || []).push({});

We find the closest point to origin in this plane by [d/[n]^2] * n. In this case n = (1,1,3); d = 7; [n]^2 = 1^2 + 1^2 + 3^2 = 11; then the vector that gives us the closest point is: (7/11, 7/11, 21/11)

I dont understand WHY this operation gives us the closest point and Strang's book doesn't really explain. I'd appreciate if you help.

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# The closest point in the plane

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