F.4 數學 - 二次方程 (高手請進)
回答 (2)
2007-10-30 6:00 am
✔ 最佳答案
(7x - 4)(3 + 4x) = (2x - 1)(4 - 7x)(7x - 4)(3 + 4x) = -(2x - 1)(7x - 4)
(7x - 4)(3 + 4x) + (2x - 1)(7x - 4) = 0
(3 + 4x + 2x - 1) (7x - 4) = 0
(6x + 2) (7x - 4) = 0
(3x + 1) (7x - 4) = 0
3x + 1 = 0 or 7x - 4 = 0
x = -1/3 or x = 4/7
2007-10-30 6:17 am
(7x - 4)(3 + 4x) = (2x - 1)(4 - 7x)
(7x - 4)(3 + 4x) = -(2x - 1)(7x - 4)
(7x - 4)(3 + 4x) + (2x - 1)(7x - 4) = 0
(3 + 4x + 2x - 1) (7x - 4) = 0
(6x + 2) (7x - 4) = 0
(3x + 1) (7x - 4) = 0
3x + 1 = 0 or 7x - 4 = 0
x = -1/3 or x = 4/7
(7x - 4)(3 + 4x) = -(2x - 1)(7x - 4)
(7x - 4)(3 + 4x) + (2x - 1)(7x - 4) = 0
(3 + 4x + 2x - 1) (7x - 4) = 0
(6x + 2) (7x - 4) = 0
(3x + 1) (7x - 4) = 0
3x + 1 = 0 or 7x - 4 = 0
x = -1/3 or x = 4/7
收錄日期: 2021-04-13 14:15:09
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