a-maths!!!!!
2007-12-18 5:32 am
Find the value of m if the roots of the quadratic equation 4x²-(5p+1)x+5p=0 differ by 1.
回答 (1)
2007-12-18 6:08 am
✔ 最佳答案
Let α and β be the roots, then we have:(α - β)2 = 1
(α + β)2 - 4αβ = 1
[(5p + 1)/4]2 - 5p = 1
(5p + 1)2 - 80p = 16
25p2 - 70p - 15 = 0
5p2 - 14p - 3 = 0
(5p + 1)(p - 3) = 0
p = 3 or -1/5
參考: My Maths knowledge
收錄日期: 2021-04-23 20:33:48
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https://hk.answers.yahoo.com/question/index?qid=20071217000051KK03800