Quadratic Equation:
Given α and β are the roots of 2x^2 +6x+3=0.
Find α^3 - β^3
α^3 - β^3
2009-10-19 1:48 am
回答 (1)
2009-10-19 2:44 am
✔ 最佳答案
A^3 - B^3 = (A - B)(A^2 + AB + B^2)= (A - B)[(A + B)^2 - AB]
= +/-√[(A + B)^2 - 4AB] * [ (A + B)^2 - AB]
Sum of roots = A+B = -6/2 = - 3
Product od roots = AB = 3/2
A^3 - B^3
= +/- √[(-3)^2 - 4(3/2)] * [ (-3)^2 - 3/2]
=(+/- √3)(15/2)
=+/- 15√3 / 2
收錄日期: 2021-04-21 22:05:50
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https://hk.answers.yahoo.com/question/index?qid=20091018000051KK01374