The axis of symmetry for a quadratic function in the standard form f(x) = ax² + bx + c can be calculated using the formula:
x = -b / (2a)
In your case, the quadratic function is:
f(x) = 3x² – 18x + 7
Here, the coefficients are:
- a = 3
- b = -18
- c = 7
Now, let’s plug the values of a and b into the axis of symmetry formula:
x = -(-18) / (2 * 3)
This simplifies to:
x = 18 / 6 = 3
Therefore, the axis of symmetry for the function f(x) = 3x² – 18x + 7 is the vertical line:
x = 3
This means that the parabola opens upwards (since a is positive), and the line x = 3 sees the graph of the function mirrored on either side of it.