Question

f(x)=x²-2x-8which statement is true1. axis of symmetry of the function is x=12.All are true3. f(x) has a minimum value of -94. f(x) has a minimum point (l,-9)

Answer 1

Given a function f(x)=x²-2x-8.

We know that the x-coordinate of the minimum point of a quadratic equation is (-b/2a).

Here, a = 1 and b = -2.

So,

`x=(-(2))/(2(1))=1`

At x = 1, the value of f(x) is -9.

`f(1)=1^2-2-8=9`

The axis of symmetry of quadratic equation x = -b/2a. So, the axis of symmetry is x = 1.

Thus, option 2 is correct.