Question

What is the value of b2 - 4ac for the following equation?

2x^2 - 2x - 1 = 0​

Answer 1

`b^2 - 4ac= 12`

Explanation:

Standard quadratic equation :

`ax^2 + bx + c = 0`

Given equation :

`2x^2 - 2x - 1 = 0`

From the given equation , a = 2, b = -2 , c = -1

Therefore,

`b^2 - 4ac= ( -2)^2 - ( 4 * 2 * (-1))`

`=4 + 8 = 12`

Answer 2

12

Explanation:

We are finding the discriminant

b^2 -4ac

2x^2 - 2x - 1 = 0​

a =2 b = -2 c = -1

(-2)^2 - 4(2)(-1)

4 +8

12