How do you covert (α−β)^2 in terms of sum and product of roots? (Sum = α+β, Product = αβ)?
回答 (2)
2017-07-25 4:42 pm
✔ 最佳答案
(α − β)² => α² - 2αβ + β²i.e. α² + β² - 2αβ
Now, (α + β)² = α² + β² + 2αβ
so, α² + β² = (α + β)² - 2αβ
=> (α − β)² = α² + β² - 2αβ = [(α + β)² - 2αβ] - 2αβ
Hence, (α + β)² - 4αβ
:)>
2017-07-25 5:19 pm
(α - β)²
= α² - 2αβ + β²
= (α² + 2αβ + β²) - 4αβ
= (α + β)² - 4αβ
= α² - 2αβ + β²
= (α² + 2αβ + β²) - 4αβ
= (α + β)² - 4αβ
收錄日期: 2021-04-18 17:33:36
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https://hk.answers.yahoo.com/question/index?qid=20170725082927AAIlG5Z