ALGEBRA Inverse Linear Functions
Content Standards A.CED.2 Create equations in two or more variables to represent relationships between quantities; graph equations on coordinate axes with labels and scales. F.BF.4a Solve an equation of the form f (x ) = c for a simple function f that has an inverse and write an expression for the inverse. Mathematical Practices 6 Attend to precision. Common Core State Standards © Copyright National Governors Association Center for Best Practices and Council of Chief State School Officers. All rights reserved.
You represented relations as tables, graphs, and mappings. Find the inverse of a relation. Find the inverse of a linear function.
Inverse Relations
Example 1 A. Find the inverse of each relation. {(−3, 26), (2, 11), (6, −1), (−1, 20)}
You Try! B. Find the inverse of each relation.
Example 2 A. Graph the inverse of each relation. Find some points that cross nicely on the graph! Flip the x and y values of those points, then graph!
You Try! B. Graph the inverse of each relation.
Finding Inverse Equations Follow these steps… 1) Replace f(x) with y! 2) Flip x and y 3) Solve for y 4) Change y back to f -1 (x)
Example 3 A. Find the inverse of the function f (x) = –3x Step 1: Step 2: Step 3: Step 4:
Example 4 You Try!
Example 5 SALES Carter sells paper supplies and makes a base salary of $2200 each month. He also earns 5% commission on his total sales. His total earnings f(x) for a month in which he compiled x dollars in total sales is f(x) = x. A. Find the inverse function.
Example 5B SALES Carter sells paper supplies and makes a base salary of $2200 each month. He also earns 5% commission on his total sales. His total earnings f(x) for a month in which he compiled x dollars in total sales is f(x) = x. B. What do x and f –1 (x)represent in the context of the inverse function?
Example 5C SALES Carter sells paper supplies and makes a base salary of $2200 each month. He also earns 5% commission on his total sales. His total earnings f(x) for a month in which he compiled x dollars in total sales is f(x) = x. C. Find Carter’s total sales for last month if his earnings for that month were $3450.
End of the Lesson Mini Practice Activity Homework: On the back of your notes sheet!