Question

Please help!!! Which is not equal to the others?

Answer 1

Answer:

b

Step-by-step explanation:

Given

a cos2x

b

2sinxcosx = sin2x

c

2cos²x - 1 = cos2x

d

1 - 2sin²x = cos2x

b is the expression not equal to the others

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Note

cos2x = cos²x - sin²x = cos²x - (1 - cos²x) = 2cos²x - 1

cos2x = (1 - sin²x) - sin²x = 1 - 2sin²x