Solution:
The curve CCC traced by QQQ is the same ellipse EEE reflected about the x-axis, x2/4+y/2=1.
Consider the ellipse E:x24+y2=1; Let PM be the ordinate of P on the first quadrant. Let Q be a point on PM such that QM is equal to length of subtangent of P. Let Q traces the curve C as P varies
The curve CCC traced by QQQ is the same ellipse EEE reflected about the x-axis, x2/4+y/2=1.