(1) (2+√5)÷3 , (2-√5)÷3
(2) (-1+√3i)÷2, (-1-√3i)÷2
Find the quadratic equation with the two given roots.
2007-11-11 9:26 pm
回答 (1)
2007-11-11 9:38 pm
✔ 最佳答案
1. Sum of roots = (2+√5)÷3 + (2-√5)÷3 = 4/3Product of roots = (2+√5)/3 * (2-√5)/3 = (4 - 5)/9 = -1/9
The equation is x^2 - (4/3) x - 1/9 = 0
i.e. 9x^2 - 12x - 1 = 0
2. Sum of roots = (-1+√3i)/2 + (-1-√3i)/2 = -1
Product roots = (-1+√3i)/2 * (-1-√3i)/2 = (1 + 3)/4 = 1
The equation is x^2 + x + 1 = 0
收錄日期: 2021-04-13 18:12:03
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https://hk.answers.yahoo.com/question/index?qid=20071111000051KK01821