tanA=2.4,要sinA and cosA

圖片參考：http://img716.imageshack.us/img716/8751/screenhunter02aug111739.gif


http://img716.imageshack.us/img716/8751/screenhunter02aug111739.gif

2010-08-11 17:43:20 補充：
補充:http://img821.imageshack.us/img821/8751/screenhunter02aug111739.gif

這裏可以幫到你
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tanA=2.4
tanA=12/5
____________
12^2+5^2=x^2(Pyth.theorem)
x.............=13
_______________
sinX:12/13

cosX:5/13


2010-08-11 14:06:40 補充：
Draw a picture!