Big Ideas Math Algebra 2, 2014
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Big Ideas Math Algebra 2, 2014 View details
1. Transformations of Quadratic Functions
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Exercise 31 Page 53

To determine the quadratic function that is obtained from the parent function, consider the transformations one at a time.

Rule: g(x)=-4x^2+2
Vertex: (0,2)

Practice makes perfect

To determine the quadratic function that is obtained from the parent function f(x)=x^2 after the given sequence of transformations, let's consider the transformations one at a time.

Vertical Stretch by a Factor of 4

We will start by performing a vertical stretch on the parent function by a factor of 4. This is done by multiplying the parent function by 4. The resulting function is y=4x^2.

Reflection in the x-axis

Next, let's reflect the function across the x-axis by multiplying the whole function by - 1.

y=4x^2 ⇔ y=-4x^2 Let's draw the graph of this function.

Vertical Translation 2 Units Up

Finally to perform a vertical translation 2 units up, we need to add 2 to the whole function. The result is g(x)=-4x^2+2.

The quadratic function that is obtained after the sequence of transformations is g(x)=-4x^2+2.

Vertex

The vertex of the quadratic parent function is (0,0). We can find the vertex of g using the transformations found above.

Transformations Change in coordinates
Vertical stretch (x, 4y)
Reflection in the x-axis (x, -4y)
Vertical translation up (x,-4y+ 2)
Let's substitute the coordinates of a parent function to find the new vertex.
(x,-4y+2)
( 0,-4( 0)+2)
(0,0+2)
(0,2)
The vertex of g(x) is (0,2).