Ask Questions, Get Answers

Want to ask us a question? Click here
Browse Questions
0 votes

The number of solutions to the equation $|x|^2+3|x|+2=0$ is

$\begin{array}{1 1}(A) \; 0 \\(B)\; 1 \\(C)\; 2 \\(D)\; 4 \end{array}$

Can you answer this question?

1 Answer

0 votes
  • If $ax^2+bx+c=0$, then $x=\large\frac{-b\pm\sqrt {b^2-4ac}}{2a}$
  • If $D=b^2-4ac\geq 0$ then the values of x are real
  • If $D=b^2-4ac< 0$ then the values of x are complex
  • $|z|$ is always a positive real number regardless of $x$ being a real number or complex number.
Given eqn. is $|x|^2+3|x|+2=0$
$\Rightarrow\:\:|x|=\large\frac{-3\pm\sqrt {9-8}}{2}$$=-2\:\:or\:-1$
But $|x|$ cannot be negative
$\therefore $ No solution exists for this equation.
answered Jul 24, 2013 by rvidyagovindarajan_1

Related questions

Ask Question
student study plans
JEE MAIN, CBSE, NEET Mobile and Tablet App
The ultimate mobile app to help you crack your examinations
Get the Android App