If a,b,c,d are in G.P, then the value of
Let y=(a−c)2+(b−c)2+(b−d)2−(a−d)2
y=a2−2ac+c2+b2−2bc+c2+b2−2bd+d2−(a2−2ad+d2)
y=2(b2−ac)+2(c2−bd)+2(ad−bc)
As a,b,c,d are in GP then b2−ac=0,c2−bd=0 and ad=bc
So y=0
If a,b,c,d are in G.P., then (a+b)2, (b+c)2, (c+d)2 are in: