If sinA + Sin2A = 1
Then prove that Cos2A + Cos4A = 1
Now from the first equation , sinA + sin2A = 1
sinA = 1 - sin2A
Using the identity( sin2A = 1 - cos2A) we get ,
sinA = cos2A
Substitute this value in the first equation , u get
sinA + sin2A = 1
cos2A + (cos2A)2 = 1
cos2A + Cos4A = 1
Hence Proved.
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