In triangle PQR, the respective length of the sides PQ and PR are denoted by u and v while the length of the median PS is denoted by w. It is known that w is the geometric mean of u and v, and Angle QPR = 60

^{o}.

Determine |cos(Angle PQR) - cos(Angle QRP)|, where |x| denotes the

absolute value of x.

(In reply to

Solution by Bractals)

Thanks Bractals.

I have hyperlinked your methodology in my solution.