JEE Main 2016 (21)

Geometry Level 4

$\cos(A-C)\cos(B)+\cos(2B)=0$ Then $a^{2},b^{2} \text{ and }c^{2}$ are in-

Clarification: $A,B \text{ and }C$ are angles of triangle, $a,b \text{ and }c$ are sides opposite to angles $A,B \text{ and } C$ respectively.