The Vertex and Axis of Symmetry
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State
The vertex is the parabola's extreme point — lowest opening up, highest opening down — and the axis of symmetry is the vertical line through it.
Show
For f(x) = x² − 4x + 3, the vertex is (2, −1) and the axis is x = 2; the halves mirror across it.
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Unlocks
- Nothing yet depends on this.