Question

If px^2+3x+q=0 has two roots x=-1 and x=-2 ,find the value of q - p . SHARE

Answer 1

PX2 + 3X + Q = 0 ------------> EQ 1
PUTTING X = 1 IN EQ 1
P(1)POWER2 + 3*1 + Q = 0
P + 3 + Q = 0
P= - Q - 3 --------> EQ 2
AGAIN, PUTTING P= - 2
P(-2) POWER 2 + 3 * -2 + Q = 0
4P - 6 + Q = 0( NOW PUT VALUE OF P FROM EQ2 TO THIS EQ)
4(- Q - 3) -6 + Q= 0
-4Q - 12 -6 + Q = 0
-3Q -18=0
Q= -18/3
Q= -6
PUTTING Q= -6 I N EQ2
P= -(-5) - 3
P= 5-3
P= 2
HENCE Q-P = -6-2
                Q-P= -8.
HOPE IT HELP