Interactive Exercise on Synthetic Substitution in Algebra Class

1. Review on A-APR.2

2. Do Now • Write down the learning goal • Get your folder and update homework log • Brainstorm an idea for slacker day

3. How to use synthetic substitution • We’ll be using this problem: Find f(3) for f(x)=5x^3+3x^2-2x+4 • 1. Draw a box for the f(x) function • 2. Write down the coefficients next to it • 3. Draw a line below that with enough space for another line of numbers. • 4. Bring down the first coefficient below the line.

4. 5. Multiply that same number by the f(x) value and write that underneath the second coefficient but above the line. • 6. Add the coefficient with the number just written and write sum directly below the line. • 7. Multiply that number by the f(x) value and write it underneath the third coefficient. • 8. Add the third coefficient with that same number and write the sum directly below that line.

5. Example problem • Find f(3) for f(x)=5x^3+3x^2-2x+4

6. Another example problem • Find f(-4) for f(x)=3x^4-2x^2+4

7. Additional practice • In the Algebra 2 books, go to page 368 • Do all problems between 13 to 20

8. Exit Ticket Find: f(-4) for f(x)=x^3+3x-5x-7

9. Homework • 2x^4-5x^2+8x-7, find f(6) • 5x^2+2x^3-3x^2+6, find f(3) • 3x-5x^3+3x^2-6x^4, find f(5)