若x+y=－√３，xy=1－√3，則x的二次+y的二次=?
回答 (2)
2015-11-10 11:51 am
✔ 最佳答案
Solx^2+y^2
=(x+y)^2－2xy
=(－√3)^2－2*(1－√3)
=3－2+2√3
=1+2√3
2015-11-10 3:50 pm
x^2+y^2=(x+y)^2-2xy
=(-3^(1/2))^(2)-2(1-3^(1/2))
=3-2+2*3^(1/2)
=1+2*3^(1/2)
=(-3^(1/2))^(2)-2(1-3^(1/2))
=3-2+2*3^(1/2)
=1+2*3^(1/2)
收錄日期: 2021-04-18 14:01:44
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20151110031127AAonKZe