Solve: 2x^2 + x + 1 = 0 - Vidyadip

Question

Solve: $2x^2 + x + 1 = 0$

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Answer

Here $2x^2 + x + 1 = 0$
Comparing the given quadratic equation with $ax^2 + bx +c= 0$, we have
a = 2, b = 1 and c = 1
$\therefore x = \frac{{ - 1 \pm \sqrt {{{(1)}^2} - 4 \times 2 \times 1} }}{{2 \times 2}}$$ = \frac{{ - 1 \pm \sqrt { - 7} }}{4} = \frac{{ - 1 \pm \sqrt 7 i}}{4}$
Thus $x = \frac{{ - 1 + \sqrt 7 i}}{4}$ and $x = \frac{{ - 1 - \sqrt 7 i}}{4}$

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