By completing the square, prove that x^2 + xy + y^2 = 0 <=> x = 0 or y = 0.
Don't know how to prove...
Thank you very much!
Pure Mathematics - Proof
2007-09-18 6:05 am
回答 (1)
2007-09-18 6:28 am
✔ 最佳答案
As follows:圖片參考：http://i117.photobucket.com/albums/o61/billy_hywung/Sep07/Crazyeqn11.jpg
2007-09-18 14:09:08 補充：
In the proof, we just use the fact and the proof can be skipped for "All square of real numbers are non-negative".
參考: My Maths knowledge
收錄日期: 2021-04-13 13:32:38
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