1) tan θ=12/13, find the value of 8 sinθ +5 cosθ / 6 sinθ +2 cosθ.
2) find the value of cos 10° - sin 80°. Evaluate the value of (cos 10°+cos 20°+......+cos 80°)-(sin 10°+sin 20°+......+sin 80°). Briefly explain how you can get the answer.
收錄日期: 2021-04-21 22:14:27
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https://hk.answers.yahoo.com/question/index?qid=20100728000051KK01382