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What is the value of (cos2 67-sin2 23°) 2 |
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Answer» value of (cos^2 67 - sin^2 23) We know,cos(90-x) = sin x Using this identity cos^2 67 - cos^2 (90-23)= cos^2 67 - cos^2 67= 0 I have used © instead of thetasin © = cos 90-©(cos^2 67° - sin^2 23°)butsin ©= cos 90-©sin 23 = cos 90-23therefore sin 23 = cos 67put this value of sin 23 in equationcos^2 67° - cos^2 67 = 0 |
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