1 Algebra I – Chapter 8 Day #1 Topic: Polynomials Standards/Goals: A.APR.1./C.1.d.: o I can determine the degree of a polynomial o I can write a polynomial in standard form o I can combine polynomials using addition and/or subtraction. Today, we focus on learning about what a polynomial is and how to identify one. Definitions: 1. Polynomial – is a monomial or a SUM of monomials. Example: Not an example: 2. Binomial – is the sum of TWO monomials. Example: 3. Trinomial – is the sum of THREE monomials. Example: NOTE: When a polynomial has THREE OR MORE terms, it does NOT have a special name. EXAMPLES: State whether each expression is a polynomial. If the expression is a polynomial, identify it as a MONOMIAL, BINOMIAL, or TRINOMIAL. 3 #1. 36 #2. 𝑞2 + 5 #3. 7x – x + 5 #4. 8𝑔2 ℎ - 7gh + 2 #5. 1 4𝑦 2 + 5𝑦 − 8 #6. 6x + 𝑥 2 #7. 7𝑎2 𝑏+ 3𝑏 2 − 𝑎2 𝑏 #8. 6𝑔2 ℎ3 𝑘 Definitions: 4. Degree – is the sum of the EXPONENTS of all its variables. Example: 5. Degree of a polynomial – is the same as the degree of the monomial with the highest degree. Example: EXAMPLES: Find the degree of each polynomial. #1. -2abc #2. 15m #3. s + 5t #4. 22 #5. 4𝑥 2 𝑦 3 𝑧 #6. 18𝑥 2 + 4yz - 10y #7. 𝑥 4 − 6𝑥 2 − 2𝑥 3 − 10 #8. 2𝑥 3 𝑦 2 − 4𝑥𝑦 3 #9. 9𝑥 2 + 𝑦𝑧 8 #10. −2𝑟 8 𝑠 4 + 7𝑟 2 𝑠 − 4𝑟 7 𝑠 6 2 We also want to learn how to write a polynomial in both descending order (standard form) and ascending order, as well. EXAMPLES: Arrange the terms of each polynomial so that the powers of x are in descending order. Descending order is typically what we consider: Standard Form. #1. 2𝑥 + 𝑥 2 − 5 #2. 20𝑥 − 10𝑥 2 + 5𝑥 3 #3. 𝑥 2 + 4𝑦𝑥 − 10𝑥 5 #4. 9𝑏𝑥 + 3𝑏𝑥 2 − 6𝑥 3 #5. 𝑥 3 + 𝑥 5 − 𝑥 2 #6. 𝑎𝑥 2 + 8𝑎2 𝑥 5 − 4 Arrange the terms of each polynomial so that the powers of x are in ascending order. Ascending order is simply another way to write a polynomial, but it is NOT in standard form. #7. 2𝑥 + 𝑥 2 − 5 #8. 6𝑥 + 9 − 4𝑥 2 #9. 4𝑥𝑦 + 2𝑦 + 6𝑥 2 #10. 6𝑦 2 𝑥 − 6𝑥 2 𝑦 + 2 #11. 𝑥 4 + 𝑥 3 + 𝑥 2 #12. 2𝑥 3 − 𝑥 + 3𝑥 7 We finally want to be able to combine polynomials using either addition or subtraction. Examples: What is the sum or difference of the two polynomials? #1. 3𝑥 2 + 5𝑥 2 #2. 4𝑥 3 𝑦 − 𝑥 3 𝑦 #3. 2𝑥 2 + 7𝑥 2 #4. 8𝑥 2 𝑦 − 3𝑥 2 𝑦 Examples: What is the simplified form of the following? #5. (2𝑥 3 + 4𝑥 2 − 3𝑥) − (6𝑥 3 + 5𝑥 2 − 4) #6. (𝑥 3 − 3𝑥 2 + 5𝑥) − (7𝑥 3 + 5𝑥 2 − 12) We also want to try a problem that incorporates a real-life situation using polynomials. EXAMPLE: The revenue generated by a company and the cost of producing ‘x’ units can be modeled by the polynomials below: REVENUE: 2𝑥 2 + 120𝑥 COST: −0.5𝑥 2 − 300𝑥 − 8000 Add the functions to determine the net profit or loss polynomial. 3 HOMEWORK – Chapter 8 Day #1 Name ________________________________ Date _______ Find the degree of each monomial. 1. 2b2c2 2. 5x 3. 7y5 4. 19ab 5. 12 1 2 z 6. 2 7. t 8. 4d4e Simplify. 9. 2a3b + 4a3b 10. 5x3 – 4x3 11. 3m6n3 – 5m6n3 12. –6ab + 3ab 13. 4c2d6 – 7c2d6 14. 315x2 – 30x2 Write each polynomial in standard form. Then name each polynomial based on its degree and number of terms. 15. 15x – x3 + 3 16. 5x + 2x2 – x + 3x4 17. 9x3 18. 7b2 + 4b 19. –3x2 + 11 + 10x 20. 12t2 + 1 – 3x + 8 – 2x Simplify. Write each answer in standard form. 21. (3k2 + 5) + (16x2 + 7) 22. (g4 – 4g2 + 11) + (–g3 + 8g) 4 23. (3a2 + a + 5) – (2a – 5) 24. (6d – 10d3 + 3d2) – (5d3 + 3d – 4) 25. (–4s3 + 2s – 3) + (–2s2 + s + 7) 26. (8p3 – 6p + 2p2) + (9p2 – 5p – 11) 27. A local deli kept track of the sandwiches it sold for three months. The polynomials below model the number of sandwiches sold, where s represents days. Ham and Cheese: Pastrami: 4s3 – 28s2 + 33s + 250 –7.4s2 + 32s + 180 Write a polynomial that models the total number of these sandwiches that were sold. 28. A pizza shop owner is monitoring the amount of cheese he uses each week. The polynomials below model the pounds of cheese ordered in the past, where p represents pounds. Mozzarella: 3p3 6p2 + 14p + 125 Cheddar: 12.5p2 + 18p + 75 Write a polynomial that models the total number of pounds of cheese that were ordered.