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补考求救呀!Gauss消去法用Gauss消去法下列解方程组

题目详情
补考求救呀!Gauss消去法
用Gauss消去法下列解方程组
▼优质解答
答案和解析
(1)+(3)-(2) ->9x2 - 2x3 = 17
x2 = 1/9 (17+2x3) ---(4)
代入(1),(3)
x1+4/9 (17+2x3) + 2x3 = 24 ---(5)
2x1 +2/3 (17+2x3) + x3 = 27 --(6)
(5)X2 -(6) => 4/9(17+2x3) + 3x3 = 21 => 35/9 x3 = 21 - 17*4/9 => x3 = 121/35
x2 = ...