WA+WB=1 WA*2.8954+WB*0.7864=5 WA? WB? 有誰會請幫幫我喔.. 謝謝!讀書討論區 回應 訪客 (未驗證) Re: 解聯立方程式 2005-05-20 17:04 WA+WB=1 WA*2.8954+WB*0.7864=5 WA? WB? <answer> WA+AB=1 ==> WA=1-WB 將此 代入 第二式 WA*2.8954 + WB*0.7864 = 5 (1-WB)*2.8954 +0.7864WB = 5 2.8954 - 2.8954WB + 0.7864WB = 5 -2.8954WB+ 0.7864WB = 5 - 2.8954 -2.109WB = 2.1046 WB= 2.1046 / -2.109 WB=-0.997913703 WA=1-WB= 1- (-0.997913703)= 1.997913703 驗算 1.997913703 * 2.8954 + 0.7864(-0.997913703 ) = 5.765813567 - 0.779613603 = 5.??? 方法是如此 小數點精確度的問題 故差一點點 ej0cl6 Re: 解聯立方程式 2005-07-14 14:13 WA+WB=1 WA*2.8954+WB*0.7864=5 WA? WB? Ans： WA+WB=1 2.8954*WA+2.8954*WB=2.8954-------1式 WA*2.8954+WB*0.7864=5-------2式 2式-1式=-2.109*WB=4 WB=-4000/2109 WA=1-WB 1-(-4000/2109)=2109/2109+4000/2109=6109/2109 WB=-4000/2109 WA=6109/2109 #
訪客 (未驗證) Re: 解聯立方程式 2005-05-20 17:04 WA+WB=1 WA*2.8954+WB*0.7864=5 WA? WB? <answer> WA+AB=1 ==> WA=1-WB 將此 代入 第二式 WA*2.8954 + WB*0.7864 = 5 (1-WB)*2.8954 +0.7864WB = 5 2.8954 - 2.8954WB + 0.7864WB = 5 -2.8954WB+ 0.7864WB = 5 - 2.8954 -2.109WB = 2.1046 WB= 2.1046 / -2.109 WB=-0.997913703 WA=1-WB= 1- (-0.997913703)= 1.997913703 驗算 1.997913703 * 2.8954 + 0.7864(-0.997913703 ) = 5.765813567 - 0.779613603 = 5.??? 方法是如此 小數點精確度的問題 故差一點點
ej0cl6 Re: 解聯立方程式 2005-07-14 14:13 WA+WB=1 WA*2.8954+WB*0.7864=5 WA? WB? Ans： WA+WB=1 2.8954*WA+2.8954*WB=2.8954-------1式 WA*2.8954+WB*0.7864=5-------2式 2式-1式=-2.109*WB=4 WB=-4000/2109 WA=1-WB 1-(-4000/2109)=2109/2109+4000/2109=6109/2109 WB=-4000/2109 WA=6109/2109 #
回應
訪客 (未驗證)
Re: 解聯立方程式
2005-05-20 17:04WA*2.8954+WB*0.7864=5
WA? WB?
<answer>
WA+AB=1 ==> WA=1-WB
將此 代入 第二式
WA*2.8954 + WB*0.7864 = 5
(1-WB)*2.8954 +0.7864WB = 5
2.8954 - 2.8954WB + 0.7864WB = 5
-2.8954WB+ 0.7864WB = 5 - 2.8954
-2.109WB = 2.1046
WB= 2.1046 / -2.109
WB=-0.997913703
WA=1-WB= 1- (-0.997913703)= 1.997913703
驗算
1.997913703 * 2.8954 + 0.7864(-0.997913703 )
= 5.765813567 - 0.779613603 = 5.???
方法是如此 小數點精確度的問題 故差一點點
ej0cl6
Re: 解聯立方程式
2005-07-14 14:13WA*2.8954+WB*0.7864=5
WA? WB?
Ans：
WA+WB=1
2.8954*WA+2.8954*WB=2.8954-------1式
WA*2.8954+WB*0.7864=5-------2式
2式-1式=-2.109*WB=4
WB=-4000/2109
WA=1-WB
1-(-4000/2109)=2109/2109+4000/2109=6109/2109
WB=-4000/2109
WA=6109/2109 #