The number of real solutions of the equation $${x^2} - 3\left| x \right| + 2 = 0\,\,{\text{is}}$$
A.
3
B.
2
C.
4
D.
1
Answer :
4
Solution :
$$\eqalign{
& {x^2} - 3\left| x \right| + 2 = 0\, \cr
& \Rightarrow \,\,{\left| x \right|^2} - 3\left| x \right| + 2 = 0 \cr
& \left( {\left| x \right| - 2} \right)\left( {\left| x \right| - 1} \right) = 0 \cr
& \left| x \right| = 1,2\,\,{\text{or }}x = \pm 1, \pm 2 \cr
& \therefore \,\,{\text{No of solution}} = 4 \cr} $$
Releted MCQ Question on Algebra >> Quadratic Equation
Releted Question 1
If $$\ell ,m,n$$ are real, $$\ell \ne m,$$ then the roots by the equation: $$\left( {\ell - m} \right){x^2} - 5\left( {\ell + m} \right)x - 2\left( {\ell - m} \right) = 0$$ are