Question

# Solve the inequality x 3 – 5x 2 + 8x – 4 > 0

A
B
C
D
##### (-∞, 1)
Solution

Correct option is

(B)

Let p , q , r are the roots of the cubic equation.

p + q + r = 5

pq+ qr+ pr = 8

pqr = 4

This happens when p = 1 , q = 2 and r = 2

if x is less than 1 , then we get negative value

if x is between 1 and 2 , then we get positive value

if x is greater than 2 , then the value is positive value

hence , the answer is , "(1,2) U (2,$infty&space;$)"

B is the correct option