If $\cos { A } +\cos ^{ 2 }{ A } =1$ , then find the value of $\sin ^{ 2 }{ A } + \sin ^{ 4 }{ A }$
cos A + cos^2A = 1
cos^2A = 1 - cos A
(1 - sin^2A) =1 - cos A
sin^2 A = cos A square both sides
sIn^4A = cos^2 A
Therefore
cos A + cos^2 A = 1
So
sin^2 A + sin^4 A = 1
