Math 0361 Test 5 Review Definitions: 1. Factored Form – An expression is written as a product of one or more terms. (Lial G-3) Example: 2x+2 = 2(x+1) 2. Common Factors(Divisors) – An integer that is a factor of two or more integers. (Lial G-1) Example: 4 and 6 have a common factor of 2. 3. Greatest Common Factor(Greatest Common Divisor) – The largest factor of all the terms of a polynomial or list of integers.(Lial G-3) Example: 12x and 30x2 have a greatest common factor of 6x. 4. Prime Polynomials – A polynomial that cannot be factored into factors having only integer coefficients.(Lial G-5) 5. FOIL Method – A method for multiplying two binomials (a+b)(c+d). (Lial G-3) Example: (a+b)(c+d)= ac +ad +bc +bd 6. Difference of Squares – The difference of two squared terms. (Lial G-2) Example: x2 – y2 = (x+y)(x-y) 7. Difference of Cubes – The difference of two cubed terms.(Lial G-2) Example: x3 – y3 = (x-y)(x2+xy+y2) 8. Sum of Cubes - The sum of two cubed terms. (Lial G-7) Example: x3+y3=(x+y)((x2-xy+y2) 9. Perfect Square Trinomial – A trinomial that can be factored as the square of a binomial.(Lial G-5) 10. Standard Form of a Quadratic Equation – an equation that can be written in the form ax2 + bx + c = 0, where a,b, and c are real numbers, with a 0. (Lial G-7) Example: 2x2 + 4x + 8 = 0 11. Zero-Factor Property – If two numbers have a product of 0, then at least one of the numbers is 0. (Lial G-8) Helpful Charts: Divisibility Chart (Lial 296): Finding the Greatest Common Factor (Lial 296): Step 1: Factor. Write each number in prime factored form. Step 2: List common factors. List each prime number or each variable that is a factor of every term in the list. (If a prime does not appear in one of the prime factored forms, it cannot appear in the greatest common factor.) Step 3: Choose least exponents. Use as exponents on the common prime factors the least exponent from the prime factored forms. Step 4: Multiply. Multiply the primes from Step 3. If there are no primes left after Step 3, the greatest common factor is 1. Factor a Polynomial with Four Terms by Grouping (Lial 300): Step 1: Group terms. Collect the terms into two groups so that each group has a common factor. Step 2: Factor within groups. Factor out the greatest common factor from each group. Step 3: Factor the entire polynomial. Factor out a common binomial factor from the results of Step 2. Step 4: If necessary, rearrange terms. If Step 2 does not result in a common binomial factor, try a different grouping. Guidelines for Factoring ax2 + bx + c (Lial 306): 1. Both integers must be positive if b and c are positive. 2. Both integers must be negative if c is positive and b is negative. 3. One integer must be positive and one must be negative if c is negative. FOIL Method: Special Factorizations (Lial 323): Solving a Quadratic Equation by Factoring (Lial 331): Step 1: Write the equation in standard form — that is, with all terms on one side of the equals sign in descending power of the variable and 0 on the other side. Step 2: Factor completely. Step 3: Use the zero-factor property to set each factor with variable equal to 0, and solve the resulting equations. Step 4: Check each solution in the original equation. Problems: 1. Complete the factoring by writing the given polynomial as the product of two factors. -14x8 =-7x3 ( ___ ) 2. Complete the factoring. 20a2b + 25a3b6 = 5a2b(______________) 3. Factor. 8x3 – 6x2 + 2x 4. Write the following in factored form by factoring out the greatest common factor. y2(x-6) + 1(x-6) 5. Is the expression in factored form or not? If it is not in factored form, factor it if possible. 17x2(y+5) + 9(y-5) 6. Factor by grouping. Y2+15x+3y+5xy 7. Factor by grouping. 7z3+7zb2+8z2b+8b3 8. Factor the given polynomial completely. If the polynomial cannot be factored, say that it is prime. x2-9x+18 9. Factor the given polynomial completely. If the polynomial cannot be factored, say that it is prime. x2+5x-14 10. Factor the given polynomial completely. If the polynomial cannot be factored, say that it is prime. x2+x+30 11. Factor the given polynomial completely. If the polynomial cannot be factored, say that it is prime. -8+7x+x2 12. Factor the given polynomial completely. If the polynomial cannot be factored, say that it is prime. b2+5bf+6f2 13. Factor the given polynomial completely. If the polynomial cannot be factored, say that it is prime. x2+13xy+40y2 14. Factor the given polynomial completely. If the polynomial cannot be factored, say that it is prime. 2x3+10x2+8x 15. Find the special product. 2 x x 3 2 3 16. Factor by grouping. 9m3-3m2p2-3mp+p3 17. Factor completely. a2-49 18. Factor the following binomial completely. If the binomial is prime, say so. 3n2+9 19. Factor completely. 36x2-25y2 20. Factor. 100s2+160sp+64p2 21. Factor. 2 3 t2+ t 1 9 22. Factor completely. 27u3+8g4 23. Factor the trinomial completely. 9x2+2x+ 1 9 24. Write the following in factored form by factoring out the greatest common factor. m(m+8n)+9n(m+8n) 25. Solve using the zero-factor property. 6s(11s+5)=0 26. Solve. w2=-18-9w 27. Solve the equation, and check your solution. 9s2+42s=-49 28. Solve the equation. (3x+4)(3x2-13x+4)=0 29. Solve the equation. y3-13y2+40y=0 30. Solve the equation. (2x-3)(x+6)=(x-6)(x+3) Works Cited Lial, Hornsby, and McGinnis. Beginning and Intermediate Algebra, 5th ed. Boston: Pearson, 2012. Print.