1) Given that tanA=3/4 and cosB= 5/ (34)^(1/2) , Show that tan(A + B) = 27/11
2) Expand cos(2A + B) and hence prove that
(1/4)cos3C=(cosC)^3 - (3/4)cosC
[15分]兩條Trigonometric functions questions
2007-07-13 8:07 pm
回答 (1)
2007-07-13 8:42 pm
✔ 最佳答案
圖片參考：http://i193.photobucket.com/albums/z215/lechocoona/maths/trigo11.gif
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