If the product of matrices A=[cos2θcosθsinθcosθsinθsin2θ],B=[cos2ϕcosϕsinϕcosϕsinϕsin2ϕ] is a null matrix, then θ−ϕ is equal to

If the product of matrices A=[cos2θcosθsinθcosθsinθsin2θ],B=[cos

1.	If the product of matrices A=[cos2θcosθsinθcosθsinθsin2θ],B=[cos2ϕcosϕsinϕcosϕsinϕsin2ϕ] is a null matrix, then θ−ϕ is equal to
Answer» If the product of matrices $A = [\begin{matrix} {cos}^{2} θ & cos θ sin θ cos θ sin θ & {sin}^{2} θ \end{matrix}], B = [\begin{matrix} {cos}^{2} ϕ & cos ϕ sin ϕ cos ϕ sin ϕ & {sin}^{2} ϕ \end{matrix}]$ is a null matrix, then $θ - ϕ$ is equal to