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*停權中*
加入日期: Aug 2013
文章: 77
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問一個三角的數學問題
1.2=5sin(a)-2sin(b-a)
-1.3=4sin(b)-2sin(a-b) ab怎樣求 |
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2015-02-04, 08:00 PM
#1
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Major Member
 加入日期: Aug 2006
文章: 207
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1.2=5sin(a)-2sin(b-a) --- 1
-1.3=4sin(b)-2sin(a-b) --- 2 令 Sin(a) = x Sin(b) = y Cos(a) = [1-x^2]^(1/2) Cos(b) = [1-y^2]^(1/2) 1: 1.2 = 5Sin(a) - 2Sin(b-a) = 5Sin(a) - 2Sin(b)Cos(a) + 2Cos(b)Sin(a) 2: -1.3 = 4Sin(b) - 2Sin(a-b) = 4Sin(b) - 2Sin(a)Cos(b) + 2 Cos(a)Sin(b) 全部帶入求解 |
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2015-02-04, 08:16 PM
#2
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