help me , very difficult !
1.prove that tan(90°+θ)≡ - 1/tanθ
2.sin(90°+θ)cos(-θ)
------------------------
cos(360°-θ)
3.
tan(180°-θ)sin(270°+θ)
------------------------------
cos(90°+θ)
F.5 MATHS 20MARKS
2010-09-27 2:33 am
回答 (1)
2010-09-27 11:31 am
✔ 最佳答案
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參考: My Maths knowledge
收錄日期: 2021-04-13 17:32:53
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