Question

Discriminant of the quadratic equation 2 x² + x - 8 = 0 is;
a) - 127
b) - 65
c) 65
d) - 15​

Answer 1

Answer :

C) 65

Solution:

⇢ 2x² + x - 8 = 0

• a = 2
• b = 1
• c =-8

D = b² - 4 ac

D = (1)² - 4 × 2 × -8

D = 1 + 64

D = 65

$\underline{\sf \therefore The\ Discriminant\ of\ above\ quadratic}\\ \underline{\sf equation\ is\ 65}$

_______________________

• Discriminant is used to find the root of the quadratic equation with the help of quadratic formula .

• Quadratic formula for an equation with root x is given by:

$\tt \: x = \frac{ - b \: \pm\sqrt{discriminant } }{2a}$

• Quadratic formula is also called Shridharacharya formula .

• There are four methods to solve quadratic equation:

1. Graphing
2. Completing the square
3. Factorisation
4. Quadratic formula

Answer 2

Answer:

ans is c

65 is right answer