Chapter 21.6
Reflection across the y-axis: y = f(-x)
What You'll Learn
Recognize that y = f(-x) creates a reflection across the y-axis
Apply the transformation by dividing all x-coordinates by negative one
Identify how positive x-values become negative x-values while y-values remain unchanged
Verify reflected graphs by substituting points into the transformed function
What You'll Practice
1
Reflecting graphs across the y-axis by transforming key points
2
Plotting reflected functions from original coordinate pairs
3
Drawing reflections of cubic and other functions using the mirror image concept
Why This Matters
Understanding reflections across the y-axis is essential for mastering function transformations, which you'll use extensively in precalculus and calculus. This skill helps you visualize symmetry, analyze even and odd functions, and solve real-world problems involving mirror images and symmetrical designs.
Before You Start — Make Sure You Can:
This Unit Includes
2 Video lessons
Learning resources
Skills
Reflections
Function Transformations
Y-axis Symmetry
Coordinate Manipulation
Graphing Functions
OH Curriculum Aligned
