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CalSuckx
Find the points on the sphere x2 + y2 + z2 = 4 that are closest to and farthest from the point (3,1,-1) .
Sphere has radius = 2 and is centered at (0, 0, 0) Draw diameter line that extends to (3,1, -1). Intersections with sphere will be closest and farthest points to (3, 1, -1).