Answer:
Vertex: ( − 2 , 3 ) Axis of Symmetry: x = − 2 Domain: R Range: R ≥ 3
Step-by-step explanation:
Explanation:
The "vertex form" for a parabola is XXX g ( x ) = m ( x − a ) 2 + b XXXXXX with the vertex at ( a , b ) To convert g ( x ) = 3 x 2 + 12 x + 15 into "vertex form" Extract the m XXX g ( x ) = 3 ( x 2 + 4 x ) + 15 Complete the square XXX g ( x ) = 3 ( x 2 + 4 x + 2 2 ) + 15 − 3 ( 2 2 ) XXX g ( x ) = 3 ( x + 2 ) 2 + 3 In complete vertex form: XXX g ( x ) = 3 ( x − ( − 2 ) ) 2 + 3 with the vertex at ( − 2 , 3 ) The equation is of the form for a parabola with a vertical axis of symmetry opening upward and since the axis of symmetry passes through the vertex, the axis of symmetry is x = − 2 g ( x ) = 3 x 2 + 12 x + 15 is defined for all Real values of x , therefore the Domain is x ∈ R . g ( x ) has values for all points at or above the vertex, therefore the Range is g ( x ) ∈ R ≥ 3 graph{3x^2+12x+15 [-7.85, 6.196, -0.84, 6.186]
