locus of midpoints in 3D
Source: 1961-62 Germany R4 12.5 https://artofproblemsolving.com/community/c3208025_
October 9, 2024
geometryLocus3D geometry
Problem Statement
Given a plane and two fixed points and that do not lie in this plane. Denote two points and on plane and the midpoints of the segments , .
a) Determine the locus of the midpoint of the segment MN if the points are and move arbitrarily in plane .
b) A circle is considered in the plane . Determine the locus of the midpoint of the segment if the points and lie on the circle or inside it .
c) is assumed to be fixed on the circle or inside it and is assumed to be movable inside it , except for . Determine the locus of the point such the above certain locus remains the same
.
Note: For b) and c) the following cases should be considered:
1. and are different,
2. and coincide.