Question

cos A + cos²A=1 then sin²+sin⁴A=​

Answer 1

Step-by-step explanation:

Answer

cosA+cos

2

A=1

cosA=1−cos

2

A

cosA=sin

2

A

Hence

sin

4

A+sin

2

A

cos

2

A+cosA

=1

Hence proved

Answer 2

cosA +cos²A= 1

⟹ cosA = 1− cos²A

⟹ cosA= sin²A

⟹ cos²A = sin⁴A

⟹ cos²A+ sin²A = sin⁴A+ sin²A = 1