First slide

Theory of equations

Question

If the equations $x^{2} + m x + 1 = 0$ and $(b - c) x^{2} + (c - a) x + (a - b) = 0$ have a common root, then

Moderate

A

$m = - 2$
B

$m = - 1$
C

$m = 0$
D

$m = 1$

Solution

As $x = 1$ satisfies
$(b - c) x^{2} + (c - a) x + (a - b) = 0$
$x = 1$ must satisfy $x^{2} + m x + 1 = 0$
$\Rightarrow 1 + m + 1 = 0 \Rightarrow m = - 2$

Get Instant Solutions

When in doubt download our app. Now available Google Play Store- Doubts App

Recieve an sms with download link

Doubts App

OR

SCAN ME

Doubts App

Doubts App