Question

若函数f(x)=ax^3+bx^2+cx+d满足f(0)=f(x1)=f(x2)=0,(0

Answer 1

f(0)=0 得出d=0 则f(x)=ax^3+bx^2+cx 则f(x)=ax^2+bx+c 两根x1 x2

【x2,……）上单调递增 所以a大于0 x1+x2>0 x1*x2>0所以