高階math-u06-d04
The locus of points equidistant from two fixed points A and B is:
A. The perpendicular bisector of AB✓ 答案
B. The circle with AB as diameter
C. The line AB itself
D. The single point that is the midpoint of AB
解說
Equidistant points form the perpendicular bisector of the segment, not just one point. The circle with AB as diameter is the locus of points where angle APB is a right angle, a different condition.