Question

Which of the following statements about the function f(x)=x2-2x-2 is true

Answer 1

Express f (x) = x^2 -2x in the form f(x) = (x - h ) ^2 - k

x^2 - 2x = +2

h = -b/2a and k = h^2

a = 1 , b= -2

h= -(-2)/ 2(1) = 2/2 = 1

k = h^2 = 1^2 = 1

So, x^2 - 2x = (x-1) ^2 - 1

To rewrite the complete equation

f(x) = (x - 1)^2 - 1 - 2

f(x) = (x - 1)^2 - 3,

`f(x)=(x-1)^2-3`

The minimum value is is -3

Option D is the answer