设关于x的方程7x^2-(k+13)x+k^2-k-2=0的根为x1和x2,满足0<x1<1<x2<2,则k的范围是?谢谢了,过程!
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方程开口向上设f(x)=7x^2-(k+13)x+k^2-k-2f(0)0 → k2或k0 → k3或k0 → k1+2/3*21^(1/2)综上 -2
设关于x的方程7x^2-(k+13)x+k^2-k-2=0的根为x1和x2,满足0<x1<1<x2<2,则k的范围是?谢谢了,过程!
方程开口向上设f(x)=7x^2-(k+13)x+k^2-k-2f(0)0 → k2或k0 → k3或k0 → k1+2/3*21^(1/2)综上 -2