Ch.9 Quadratic Functions and Equations
Alg 1B Sec 9.2 Quadratic Functions
notes
Quadratic Function (Standard Form)
𝒚 = 𝒂𝒙² + 𝒃𝒙 + 𝒄
Vertex (
𝒂≠𝟎
−𝒃
𝟐𝒂
, ____)
Axis of symmetry 𝒙 =
−𝒃
𝟐𝒂
Domain – Possible input (x’s) All Real Numbers
Range – Possible output (y’s) 𝒚 ≥ 𝒎𝒊𝒏
or
𝒚 ≤ 𝒎𝒂𝒙
Ex.1: Find the equation of the axis of symmetry and the vertex for each parabola.
a. f  x   3x 2  6 x  5
Vertex:__________
Axis of Symmetry:_______
b. y  x2  4 x  6
Vertex:___________
Axis of Symmetry:_______
Ex.2: Find the vertex, axis of symmetry,domain and range. Graph the function.
y   x2  4x  2
Vertex:_____
Domain_______________
A of S:______
x
Range________________
y
Ex.3: Find the vertex, axis of symmetry,domain and range. Graph the function.
f  x   3x 2  6 x  2
Vertex:_____
Domain_______________
A of S:______
x
Range________________
y
Ex.4: Find the vertex, axis of symmetry,domain and range. Graph the function.
f  x   2 x 2  8 x  3
Vertex:_____
A of S:______
x
y
p576: 9-15odd, 16-23all, 30
Domain_______________
Range________________