Discriminant of the following quadratic equation is :
$x^{2} - 2 x - 4 = 0$

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Solution

$\Rightarrow$ The given quadratic equation is $x^{2} - 2 x - 4 = 0$ , comparing it with $a x^{2} + b x + c = 0$
$\Rightarrow$ We get, $a = 1, b = - 2$ and $c = - 4$
$\Rightarrow$ $D = b^{2} - 4 a c$
$= (- 2)^{2} - 4 (1) (- 4)$
$= 4 + 16$
$= 20$
$∴$ Discriminant of the given quadratic equation is $20$ .

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Discriminant of the following quadratic equation is :x2−2x−4=0

⇒ The given quadratic equation is x2−2x−4=0, comparing it with ax2+bx+c=0⇒ We get, a=1,b=−2 and c=−4⇒ D=b2−4ac =(−2)2−4(1)(−4) =4+16 =20∴ Discriminant of the given quadratic equation is 20.

Discriminant of the following quadratic equation is :
$x^{2} - 2 x - 4 = 0$