Question
Solve the following quadratic equation using formula method only
$x ^2+\frac{1}{2} x -1=0$
$x ^2+\frac{1}{2} x -1=0$
✓
Answer
$x ^2+\frac{1}{2} x -1=0 $
$ 2 x ^2+ x -2=0$
$ a =2 ; b =1 ; c=-2 $
$D = b ^2-4 ac$
$=(1)^2-4(2)(-2) $
$=1+16$
$ =17 $
$ x =\frac{- b \pm \sqrt{ b ^2-4 ac }}{2 a} $
$ x =\frac{-1 \pm \sqrt{17}}{4} $
$x =\frac{-1+\sqrt{17}}{4}, x=\frac{-1-\sqrt{17}}{4}$
$ 2 x ^2+ x -2=0$
$ a =2 ; b =1 ; c=-2 $
$D = b ^2-4 ac$
$=(1)^2-4(2)(-2) $
$=1+16$
$ =17 $
$ x =\frac{- b \pm \sqrt{ b ^2-4 ac }}{2 a} $
$ x =\frac{-1 \pm \sqrt{17}}{4} $
$x =\frac{-1+\sqrt{17}}{4}, x=\frac{-1-\sqrt{17}}{4}$
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