help! 50 POINTS show work please but if not it’s okay
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Answer:
The answer is cos2x - sin2x - sin x.
Use the rule: cos2x = (cos^2)x - (sin^2)x. So, substitute cos2x in the expression: cos2x - sinx = ((cos^2)x - (sin^2)x) - sinx = (cos^2)x - (sin^2)x - sinx.
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