Write the number of real roots of the equation

Question:

Write the number of real roots of the equation $x^{2}+3|x|+2=0$.

Solution:

The given quadric equation is $x^{2}+3|x|+2=0$

$x^{2}+3|x|+2=0$

Here, $a=1, b=\pm 3$ and, $c=2$

As we know that $D=b^{2}-4 a c$

Putting the value of $a=1, b=\pm 3$ and, $c=2$

$=(\pm 3)^{2}-4 \times 1 \times 2$

$=9-8$

$=1$

Since, $D \geq 0$

Therefore, roots of the given equation are real and distinct.

$\therefore$ The number of real roots of the given equation is 4 .

Leave a comment