# “Rationally” Sketching Functions – App Lesson

Description: This app lesson will develop high school students’ knowledge and ability to sketch, plot, and understand rational functions.

Instructional Objective: Students will be able to sketch rational functions, noting the x and y intercepts, asymptotes, and the locations of curves.

Step 1: Students will watch this video in which the graph

is sketched, solving algebraically the following: the x and y intercepts, horizontal asymptotes, vertical asymptotes, then sketching the curves using knowledge of end behavior in the Khan Academy app.

Step 2: Students will graph the following three rational functions using the Desmos Graphing Calculator, noting the points of interest mentioned above. They will also sharpen their skills of entering in information into a graphing calculator, noting how parentheses affect their inputs. Note: one of the functions will have a “hole” in it.

Step 3:  Students will join our classroom in the ShowMe app. Then students will import the assignment template I have previously made and sketch their rational function onto the template (which is lined like graph paper). Students will then compare their answers with a partner. Students will also do a voice recording in which they will talk about what they did at each step to be able to graph this function. Students will then upload their drawing and recording into the classroom group. After they have completed this task, they will be able to view other students’ notes.

Step 4:  Students will participate in a closing activity by playing a Kahoot quiz in which students will match 2 rational functions with their corresponding graphs.

Inspired by Clara Grace Coker