यदि `cos alpha+cos beta=sin alpha +sin beta=0,` तो `cos 2alpha+cos beta=`

If cos alpha+cos beta=0=sin alpha+sin beta then cos2 alpha+cos2 beta=

If cos alpha+cos beta=0=sin alpha+sin beta , then cos 2 alpha+cos 2beta is equal to

A = [[0, sin alpha, sin alpha sin beta-sin alpha, 0, cos alpha cos beta-sin alpha sin beta, -cos alpha cos beta, 0]]

If cos alpha+cos beta=0=sin alpha+sin beta, then cos2 alpha+cos2 beta is equal to

If cos alpha + cos beta =0 = sin alpha + sin beta , then cos 2 alpha + cos 2 beta is equal to

If cos alpha+cos beta=0=sin alpha+sin beta, then cos2 alpha+cos2 beta is equal to (a)-2sin(alpha+beta)(b)-2cos(alpha+beta)(c)2sin(alpha+beta)(d)2cos(alpha+beta)

2 sin ^(2) beta + 4 cos (alpha + beta) sin alpha sin beta + cos 2 (alpha + beta )=

If cos alpha+cos beta=0=sin alpha+sin beta. Prove that cos2 alpha+cos2 beta=-2cos(alpha+beta)