Question

solve the following
cos^2 theta -sin^2 theta =2 cos^2 theta -1
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Answer 1

Step-by-step explanation:

cos^2A-sin^2A

• 1/2(2cos^2A - 2sin^2A)
• 1/2(1+cos2A-1+cos2A)
• 1/2×2cos2A
• 2cos^2A-1