十万火急~已知:x1<x2<x3,y1<y2<y3 x1+x2+x3=y1+y2+y3 x1x2+x2x3+x3x1=y1y2+y2y3+y3已知:x1<x2<x3,y1<y2<y3x1+x2+x3=y1+y2+y3x1x2+x2x3+x3x1=y1y2+y2y3+y3y1若x1<y1求证;x2>y2且x3小于y3我一点思路也没有,麻烦把过
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![十万火急~已知:x1<x2<x3,y1<y2<y3 x1+x2+x3=y1+y2+y3 x1x2+x2x3+x3x1=y1y2+y2y3+y3已知:x1<x2<x3,y1<y2<y3x1+x2+x3=y1+y2+y3x1x2+x2x3+x3x1=y1y2+y2y3+y3y1若x1<y1求证;x2>y2且x3小于y3我一点思路也没有,麻烦把过](/uploads/image/z/4482632-56-2.jpg?t=%E5%8D%81%E4%B8%87%E7%81%AB%E6%80%A5%7E%E5%B7%B2%E7%9F%A5%EF%BC%9Ax1%EF%BC%9Cx2%EF%BC%9Cx3%2Cy1%EF%BC%9Cy2%EF%BC%9Cy3+x1%2Bx2%2Bx3%3Dy1%2By2%2By3+x1x2%2Bx2x3%2Bx3x1%3Dy1y2%2By2y3%2By3%E5%B7%B2%E7%9F%A5%EF%BC%9Ax1%EF%BC%9Cx2%EF%BC%9Cx3%2Cy1%EF%BC%9Cy2%EF%BC%9Cy3x1%2Bx2%2Bx3%3Dy1%2By2%2By3x1x2%2Bx2x3%2Bx3x1%3Dy1y2%2By2y3%2By3y1%E8%8B%A5x1%EF%BC%9Cy1%E6%B1%82%E8%AF%81%EF%BC%9Bx2%EF%BC%9Ey2%E4%B8%94x3%E5%B0%8F%E4%BA%8Ey3%E6%88%91%E4%B8%80%E7%82%B9%E6%80%9D%E8%B7%AF%E4%B9%9F%E6%B2%A1%E6%9C%89%2C%E9%BA%BB%E7%83%A6%E6%8A%8A%E8%BF%87)
十万火急~已知:x1<x2<x3,y1<y2<y3 x1+x2+x3=y1+y2+y3 x1x2+x2x3+x3x1=y1y2+y2y3+y3已知:x1<x2<x3,y1<y2<y3x1+x2+x3=y1+y2+y3x1x2+x2x3+x3x1=y1y2+y2y3+y3y1若x1<y1求证;x2>y2且x3小于y3我一点思路也没有,麻烦把过
十万火急~已知:x1<x2<x3,y1<y2<y3 x1+x2+x3=y1+y2+y3 x1x2+x2x3+x3x1=y1y2+y2y3+y3
已知:x1<x2<x3,y1<y2<y3
x1+x2+x3=y1+y2+y3
x1x2+x2x3+x3x1=y1y2+y2y3+y3y1
若x1<y1
求证;x2>y2且x3小于y3
我一点思路也没有,麻烦把过程写得清楚一点,
十万火急~已知:x1<x2<x3,y1<y2<y3 x1+x2+x3=y1+y2+y3 x1x2+x2x3+x3x1=y1y2+y2y3+y3已知:x1<x2<x3,y1<y2<y3x1+x2+x3=y1+y2+y3x1x2+x2x3+x3x1=y1y2+y2y3+y3y1若x1<y1求证;x2>y2且x3小于y3我一点思路也没有,麻烦把过
构造函数f(x)=(x-x1)(x-x2)(x-x3)=x^3-(x1+x2+x3)x^2+(x1x2+x2x3+x3x1)x-x1x2x3,其图像与x轴交于三点(x1,0),(x2,0),(x3,0)
g(x)=(x-y1)(x-y2)(x-y3)=x^3-(y1+y2+y3)x^2+(y1y2+y2y3+y3y1)x-y1y2y3,其图像与x轴交于三点(y1,0),(y2,0),(y3,0)
因为x1+x2+x3=y1+y2+y3
x1x2+x2x3+x3x1=y1y2+y2y3+y3y1
且x1<y1
所以只需将f(x)的图像向下平移就可得g(x)的图像,有图像知,x2>y2且x3小于y3