设x1,x2是方程x²-x+1=0的二个虚数根,则(x1)²+(x2)²=? 麻烦细节写出.
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![设x1,x2是方程x²-x+1=0的二个虚数根,则(x1)²+(x2)²=? 麻烦细节写出.](/uploads/image/z/11505984-24-4.jpg?t=%E8%AE%BEx1%2Cx2%E6%98%AF%E6%96%B9%E7%A8%8Bx%26%23178%3B-x%2B1%3D0%E7%9A%84%E4%BA%8C%E4%B8%AA%E8%99%9A%E6%95%B0%E6%A0%B9%2C%E5%88%99%28x1%29%26%23178%3B%2B%28x2%29%26%23178%3B%3D%3F+%E9%BA%BB%E7%83%A6%E7%BB%86%E8%8A%82%E5%86%99%E5%87%BA.)
设x1,x2是方程x²-x+1=0的二个虚数根,则(x1)²+(x2)²=? 麻烦细节写出.
设x1,x2是方程x²-x+1=0的二个虚数根,则(x1)²+(x2)²=? 麻烦细节写出.
设x1,x2是方程x²-x+1=0的二个虚数根,则(x1)²+(x2)²=? 麻烦细节写出.
x1+x2=1
x1x2=1
(x1)²+(x2)²
=(x1+x2)²-2x1x2
=-1
x1+x2=-b/a=1,x1x2=c/a=1
(x1)²+(x2)²=(x1+x2)^2- 2x1x2 =1-2×1=-1