- Home
- Standard 11
- Mathematics
Solve the equation $x^{2}+x+\frac{1}{\sqrt{2}}=0$
$\frac{-1 \pm(\sqrt{2 \sqrt{2}-1}) i}{2}$
$\frac{-1 \pm(\sqrt{2 \sqrt{2}-1}) i}{2}$
$\frac{-1 \pm(\sqrt{2 \sqrt{2}-1}) i}{2}$
$\frac{-1 \pm(\sqrt{2 \sqrt{2}-1}) i}{2}$
Solution
The given quadratic equation is $x^{2}+x+\frac{1}{\sqrt{2}}=0$
This equation can also be written as $\sqrt{2} x^{2}+\sqrt{2} x+1=0$
On comparing the given equation with $a x^{2}+b x+c=0,$
we obtain $a=\sqrt{2}, b=\sqrt{2},$ and $c=1$
$\therefore $ Discriminant $(D)=b^{2}-4 a c=(\sqrt{2})^{2}-4 \times(\sqrt{2}) \times 1=2-4 \sqrt{2}$
Therefore, the required solutions are
$\frac{-b \pm \sqrt{D}}{2 a}=\frac{-\sqrt{2} \pm \sqrt{2-4 \sqrt{2}}}{2 \times \sqrt{2}}=\frac{-\sqrt{2} \pm \sqrt{2(1-2 \sqrt{2})}}{2 \sqrt{2}}$
$=\left(\frac{-\sqrt{2} \pm \sqrt{2}(\sqrt{2 \sqrt{2}-1}) i}{2 \sqrt{2}}\right) \quad[\sqrt{-1}=i]$
$=\frac{-1 \pm(\sqrt{2 \sqrt{2}-1}) i}{2}$