Question

if sin theta+sin square theta=1 then show that cos square theta+cos power 4 theta=1
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Answer 1

Step-by-step explanation:

sin theta + sin² theta = 1

=> sin theta = 1 - sin²theta

=> sin theta = cos²theta --- (sin²theta+cos²theta = 1)

=> cos²theta + cos4theta = cos²theta + (cos²theta)²

=>cos²theta + cos4theta = sin theta + sin4theta = 1

Hence Proved.