4xa0a2的精選

問題詳情：設函數f(x)=x3-4x+a(0<a<2)有三個零點x1,x2,x3,且x1<x2<x3,則下列結論正確的是()A.x1>-1               B.x2<0C.x3>2                    D.0<x2<1【回答】D.因為函數f(...