Let `f(x)=ax^3+bx^2+x+d` has local extrema at `x=alpha and beta` such that `alphabetalt0 and f(alpha
Channel: Doubtnut
Date: 05/04/2020

Let `f(x)=ax^3+bx^2+x+d` has local extrema at `x=alpha and beta` such that `alphabetalt0 and f(alpha).f(beta)gt0`. Then the equation `f(x)=0` (A) has 3 distinct real roots (B) has only one real which is positive o `a.f(alpha)lt0` (C) has only one real root, which is negative `a.f(beta)gt0` (D) has 3 equal roots