Question

If sinA+sin²A= 1, then show that: cos²A+cos⁴A= 1.​

Answer 1

Answer:

sinA+sin²A=1

sinA= 1-sin²A=cos²A

square both sides,

sin²A=cos⁴A

1-cos²A=cos⁴A

cos²A+cos⁴A=1

proved.

mark as Brainlist answer.

Answer 2

Answer:

sinA+sin2A=sin2A+cos2A

sinA=cos2A

substitute in the question

cos4A=sin2A

sinA+sin2A=cos2A+cos4A=1

hence proved