Question

Find the value of discriminant for the quadratic equation 2y2 - y + 2 = 0 *

1. 12

2. -12

3. -15

4. 15

​

Answer 1

Answer:

D=b^2-4ac

D=(-1)^2-4(2)(2)

D=1-16

D=-15

Answer 2

$\blue{\bold{\underline{\underline{Answer:}}}}$

$\green{\tt{\therefore{Discriminant=-15}}}$

$\orange{\bold{\underline{\underline{Step-by-step\:explanation:}}}}$

$\green{\underline \bold{Given :}} \\ \tt: \implies {2y}^{2} - y+ 2 = 0 \\ \\ \red{\underline \bold{To \: Find :}}\\ \tt: \implies Discriminant = ?$

• According to given question :

$\tt \circ \: a = 2 \: \: \: \: \: \: b = - 1 \: \: \: \: \: \: c = 2 \\ \\ \bold{As \: we \: know \: that} \\ \tt: \implies Discriminant = {b}^{2} - 4ac \\ \\ \tt: \implies Discriminant = ( - 1)^{2} - 4 \times 2 \times 2 \\ \\ \tt: \implies Discriminant = 1 - 16 \\ \\ \green{\tt: \implies Discriminant = - 15}\\\\ \blue{\bold{Some \: related \: formula}} \\ \orange{\tt \circ \: x = \frac{ - b \pm \sqrt{ {b}^{2} - 4ac } }{2a} }$