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 32 Page 53

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

Rule: g(x)=1/3(x-3)^2
Vertex: (3,0)

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 Shrink by a Factor of 13

We will start by performing a vertical shrink on the parent function by a factor of 13. This is done by multiplying the parent function by 13. The resulting function is y= 13x^2.

Reflection in the y-axis

Next, let's reflect the function across the y-axis by multiplying the variable by -1.

y=1/3(- x)^2 ⇔ y=1/3x^2 Notice, in this case the function does not change because (- x)^2=x^2.

Horizontal Translation 3 Units Right

Finally, to perform a horizontal translation 4 units right we need to subtract 3 from the x-variable. The result is g(x)= 13(x-3)^2.

The quadratic function that is obtained after the sequence of transformations is g(x)= 13(x-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 shrink (x, 1/3y)
Reflection in the y-axis ( -x,1/3y)
Horizontal translation right (- x+ 3,1/3y)
Let's substitute the coordinates of a parent function to find the new vertex.
(- x+3,1/3y)
(- 0+3,1/3( 0))
(-0+3,0)
(3,0)
The vertex of g(x) is (3,0).