2.1 Transformers: Shifty y’s A Develop Understanding Task Review finding the area of a rectangle and square. Optima is designing a robot quilt for her new grandson. She plans for the robot to have a square face. The amount of fabric that she needs for the face will depend on the area of the face, so Optima decides to model the area of the robot’s face mathematically. She knows that the area A of a square with side length x is modeled by the function What is the domain of the function A(x) in context? Whole class: Use a square of length 3. Small groups: Use a square of length x. Given the square above find the area under the given changes and draw a picture of the new square. a. Length of any given side is increased by 5 units b. Length of any given side is multiplied by 5 units c. Area of a square is increased by 5 square units. d. Area of a square is multiplied by 5.
x -2 -1 1 2 x -2 -1 1 2 x -2 -1 1 2 We need graphing calculators. 4. Optima decides find how changes to the equation change the graphs. She thinks that it is always a good idea to start simple, so she decides to go with � y = x2 + 5 and y = x2 - 3. Complete the chart and draw a graph for the parent function and the two new functions. Describe what you find. Are their patterns to the changes? x -2 -1 1 2 x -2 -1 1 2 x -2 -1 1 2
What conclusion would you draw about the effect of adding/subtracting a number to the function? Describe how the function is changed by .
Describe how each graph moved from the parent function. 6. After her amazing success with addition in the last problem, Optima decides to look at what happens with addition and subtraction inside the parentheses, or as she says it, “adding to the x before it gets squared”. Using your technology, decide the effect of h in the equations: y = (x + ℎ)2 and y = (x − ℎ)2. (Choose some specific numbers for h.) Record a few examples (both tables and graphs) in your notebook and explain why this effect on the graph occurs. X -3 -2 -1 1 2 3 Describe how each graph moved from the parent function. What part of the equation shows this move?
7. Optima thought that #6 was very tricky and hoped that multiplication was going to be more straightforward. She decides to start simple and multiply by -1, so she begins with y = −�x2. Predict what the effect is on the graph and then test it. Why does it have this effect? Complete the chart and draw a graph for the parent function and the new function. x -2 -1 1 2 x -2 -1 1 2
8. Optima is encouraged because that one was easy 8. Optima is encouraged because that one was easy. She decides to end her investigation for the day by determining the effect of a multiplier, a, in the equation: y = ax2. Using both positive and negative numbers, fractions and integers, create at least 3 tables and matching graphs to determine the effect of a multiplier. x -2 -1 1 2 x -2 -1 1 2 x -2 -1 1 2 Describe the effect of the multiplier a on the graph of the function.
Vocabulary Define or label these parts of a parabola. Vertex Axis of Symmetry Maximum or Minimum Open up Open down Complete Ready and Set for Lesson 2.1
Closure – Summarize the effect of the 4 types of transformations studied today. Describe the change to the function, coordinates, and graph. Adding/subtracting a number to the function Replacing x with x – h or x + h in the function. Multiplying the function by -1. Multiply by a factor