Given two points A(-1, 0) and B(1, 0) on the coordinate plane, and a moving point P whose sum of distances to points A and B is a constant 2, the trajectory of point P is
Pick one
Solution
From the given information, we know that the distance between points A(-1, 0) and B(1, 0) is 2.
Since the sum of distances from the moving point P to points A and B is a constant 2,
it follows that , which means the moving point P is moving along the line segment AB.
Therefore, the trajectory of point P is a line segment.
Hence, the correct choice is .
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