The range of values of so that all the roots of the equation are real and distinct

MATHEMATICS · Single correct · AP · Calculus AB · Analytical Applications of Differentiation · Analytical Applications of Differentiation

Problem

The range of values of

a

so that all the roots of the equation

2x^3 - 3x^2 - 12x + a = 0

are real and distinct, belongs to (1)

(7, 20)

(2)

(-7, 20)

(3)

(-20, 7)

(4)

(-7, 7)