Question

Given that a = 2 , b = − 1 and c = 3 work out b squared − 2 a c

Answer 1

Explanation:

Write "b squared − 2 a c" as b^2 - 4ac.

Now, given that a = 2 , b = − 1 and c = 3

we have (-1)^2 - 4(2)(3), or -23.

If you really meant "b squared − 2 a c" then the end result would be different:

(-1)^2 - 2(2)(3), or -11

Note that "b^2 - 4ac" is the formula for the discriminant of a quadratic equation, whereas "b squared − 2 a c" is not.

Answer 2

-11

Explanation:

b^2 -2ac

= (-1)^2 - 2*2*3

= 1 - 12

= -11