If sinA + sin2A = 1, what is the value of cos2 + cos4A = ?
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B.
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sinA + sin2A = 1
sinA = 1 - sin2A
sinA = cos2A
cos2A + cos4A = cos2A + (cos2A)2
= sinA + sin2A = 1
ABC is a right angled triangle with Then the value of cos2A + cos2B + cos2C is:
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