Question

How do you find the axis of symmetry, and the maximum or minimum value of the function `y=x^2 - 3`?

Answer 1

Maximum value is `(0,-3)`
And axis of symmetry is the y axis.

Explanation:

Comparing with `y=ax^2+bx+c`
`a=1`
`b=0`
`c=-3`

Axis of symmetry of a parabola is `x=x_(max)`

So,
`x_(max)=-b/(2a)`
`=0/(2×1)`
`=0`
Hence axis of symmetry is `x=0`
Evaluate `x=0` to get maximum.
Thank you