Putnam 1946 A1. R is the reals. The distances of a point P in space from A, B, C, D are a, b, c, d respectively.
R is the reals.
Show that f is constant. A particle moves in one dimension. Two circles C 1 and C 2 intersect at A and B. C 1 has radius 1. L denotes the arc AB of C 2 which lies inside C 1 . L divides C 1 into two parts of equal area.