If (mi,1mi),i=1,2,3,4 are concyclic points then the value of m1m2m3m4 is?
If (mi,1mi), i = 1, 2, 3, 4 are con - cyclic points, then the value of m1m2m3m4 is
if (mi,1mi), i=1,2,3,4 are four distinct points on a circle, then m1m2m3m4=