Reflection: Complex Tasks Graphs of Cubic Functions - Section 3: Explaining the Solution


This problem is complex and challenging because students must remember to verify the y-intercept.  Once they three linear factor are in place, they have a complete cubic equation.  However, they must take the time to check whether or not the graph of their equation will include the fourth given point!

This example of work from one of my students who did not think to do this!  It wouldn't be a big deal, but once this had been clearly explained in class he should have corrected his work.  When I saw this mistake, I immediately thought, "Oh, no!  He's still confused about this! Wasn't he there when we discussed this?"  However, it turned out that he solved the next two problems correctly, so I guess that this was simply an oversight on his part.  Next time, I'll remind everyone that they should be assessing their own work and correcting their own mistakes after we discuss the solution.

  Complex Tasks: Are they listening?
Loading resource...

Graphs of Cubic Functions

Unit 3: Cubic Functions
Lesson 9 of 13

Objective: SWBAT write an equation for a cubic function from a graph with given roots. SWBAT explain how the factor theorem helps them write a cubic equation.

Big Idea: How many points does it take to determine a cubic function? Four - and it helps if three of them are roots!

  Print Lesson
Math, cubic equations, polynomial equation, Graphing (Algebra), factor theorem, Algebra 2, master teacher project, cubic functions, Algebra 2, function
  45 minutes
graphs of cubics image
Similar Lessons
Sketching Graphs of Polynomial Functions
12th Grade Math » Polynomial and Rational Functions
Big Idea: Build upon existing knowledge of second and third degree functions to sketch graphs of other polynomial functions.
Troy, MI
Environment: Suburban
Tim  Marley
Choosing a Method to Find x-intercepts
Algebra I » Quadratics!
Big Idea: Students take a step back from their work to examine a variety of quadratic functions and reflect on why they might choose one method over another.
Boston, MA
Environment: Urban
Amanda Hathaway
Rational Roots and Remainders: Important Theorems of Polynomials
12th Grade Math » Polynomial Functions and Equations
Big Idea: Using polynomial division students discover the Remainder Theorem & then learn about the Rational Root Test.
Phoenix, AZ
Environment: Urban
Tiffany Dawdy
Something went wrong. See details for more info
Nothing to upload