16 Days Two Days Review - Use FOIL and the Distributive Property to multiply polynomials. ( x 3)( x 5) (2 x 1)( x 5) Writing a polynomial as a product of its factors. Essentially undoing the multiplication. Purposes of factoring: ◦ Simplifying ◦ Rewriting ◦ Solving x 10 x 24 2 x 16 2 GCF Grouping Difference of Squares Difference of Squares Formula a b (a b)( a b) 2 2 Perfect Square Trinomials x 6x 9 2 4 x 4 xy y 2 2 Perfect Square Trinomial Formulas a 2ab b (a b) 2 a 2ab b (a b) 2 2 2 2 2 Trinomials (a=1) Trinomials (a≠1) 2 x 5x 3 2 6x x 2 2 Sum and Difference of Cubes Formulas x y ( x y)( x 2 xy y ) 3 3 2 2 x y ( x y)( x 2 xy y ) 3 3 2 2 Sum and Difference of Cubes pg 263 (# 2-30 even) x 7x 6 2 x 16 2 x 3 x 18 2 x 11x 18 2 2x 9x 4 2 x 9x 3 2x 6x 4 2 10 x 13 x 3 2 6 x 5x 6 2 16 x 25 2 Two Days Question: How can we multiply two or more numbers together and get a product that equals zero? For any real numbers a and b, if ab=0, then either a=0, b=0, or both. x 32x 1 0 x 3 0 or 2x 1 0 x 3 or 2x 1 1 x 3 or x 2 The solutions are -3 and 1/2. 2 9x 4 0 Factor using “difference of two squares.” 3x 23x 2 0 3x 2 0 or 3x 2 0 3x 2 or 3x 2 2 2 x or x 3 3 2 x 27 6x 2 x 6x 27 0 x 9x 3 0 x 9 0 or x 3 0 x 9 or x 3 2 2x 8x 0 2x x 4 0 2x 0 or x 4 0 x 0 or x 4 Did you take out GCF? 1. 3y 52y 7 0 2 2. x x 12 2 3. d 5d 0 4. 4c 25 2 5. 18u 1 3u 2 1. y 5 3 or y 7 2 2. x 4 or x 3 3. d 0 or d 5 4. 5. c 5 2 or c 5 2 u 1 6 or u 1 3 If all are correct, you’re finished! 3y 52y 7 0 3y 5 0 or 2y 7 0 3y 5 or 2y 7 y 5 3 or y 7 2 Back to questions 2 x x 12 2 x x 12 0 x 4 x 3 0 x 4 0 or x 3 0 x 4 or x 3 Back to questions d 5d 0 2 d d 5 0 d 0 or d 5 0 d 0 or d 5 Back to questions 4c2 25 4c 25 0 2 2c 52c 5 0 2c 5 0 or 2c 5 0 2c 5 or 2c 5 c 5 2 or c 5 2 Back to questions 2 18u 3u 1 2 18u 3u 1 0 6u 13u 1 0 6u 1 0 or 3u 1 0 6u 1or 3u 1 u 1 6 or u 1 3 Back to questions One Day Two Days Solve the following quadratic: x2 4 0 The Imaginary Unit (i) has the following properties. The imaginary number i is defined as the number whose square is -1. That is: Imaginary Numbers are of the form a + bi where b ≠ 0. Complex Numbers are of the form a + bi where a and b are Real Numbers. We can add and subtract imaginary numbers similar to how we add and subtract terms with variables. Think “like terms.” Similarly, we can multiply imaginary numbers following the same exponent rules we use for variables. The absolute value of a complex number is the distance the number lies from the origin in the complex plane. Think Pythagorean Thm.. a bi a 2 b2 Larger powers of i can be simplified by dividing the power by 4 and using the remainder to determine the appropriate value. Solve: 5 x 2 200 0 Pg 278 (# 1-45 odd) If z = a + bi is an imaginary number, the its conjugate is z = a – bi. Complex Conjugates can be used to eliminate imaginary numbers from the denominators of fractions. This is very similar to how we rationalize denominators. Eliminate the Imaginary numbers from the denominator in the following example. Practice 5-6 WS (even) Two Days Examples x2 + 6x + 9 x2 - 10x + 25 x2 + 12x + 36 In the following perfect square trinomial, the constant term is missing. X2 + 14x + ____ Find the constant term by squaring half the coefficient of the linear term. (14/2)2 X2 + 14x + 49 ax 2 bx c 0 b b 2 4ac Quardatic Formula : x 2a Solve the following using the quadratic formula: x2 6x 5 0 2 x 2 3x 9 0 What do we notice about these two problems? How else could we Have solved these quadratics? Solve the following quadratics: 3x 2 10 x 5 0 3 x 2 4 x 10 0 pg 293 (# 1-29 odd) 1 Day 1. When you solve using completing the square on the general formula ax 2 bx c 0 you get: b b2 4ac x 2a 2. This is the quadratic formula! 3. Just identify a, b, and c then substitute into the formula. The quadratic formula allows you to solve ANY quadratic equation, even if you cannot factor it. An important piece of the quadratic formula is what’s under the radical: b2 – 4ac This piece is called the discriminant. The discriminant tells you the number and types of answers (roots) you will get. The discriminant can be +, –, or 0 which actually tells you a lot! Since the discriminant is under a radical, think about what it means if you have a positive or negative number or 0 under the radical. Value of the Discriminant Nature of the Solutions Negative 2 imaginary solutions Zero 1 Real Solution Positive – perfect square 2 Reals- Rational Positive – non-perfect square 2 Reals- Irrational x2 4x 5 0 2 x 2 x 28 0 6x2 2x 5 0 x 2 12 x 36 0 Pg 293 (#31-39 odd) Practice 5-8 WS (#2-26 even) Quiz 5.8 on 11/18!! 1 Day The standard form of a quadratic is y ax bx c where : 2 2 ax is the quadratic term, bx is the linear ter m, and c is the constant t erm. The graph of a quadratic function is called a parabola. The axis of symmetry is the vertical line that divides the parabola into two identical halves and is written x=a. The vertex (a,b) of the parabola is the point at which the parabola intersects the axis of symmetry and is also a maximum or minimum point of the function. Given 3 points on the function we can determine the equation of the quadratic. Find y ax bx c where : (1,0), (2,3), and (3,10) are points on the function. 2 pg. 241 (#1-12 all, 21) 4 Days 3 Days Standard form of a Quadratic: y ax bx c ; a 0 2 Vertex form of a Quadratic: y a( x h) 2 k ; Vertex : (h, k ) y 3x 2 6 x 4 y 3( x 2 2 x )4 y 3( x 2 2 x (1) 2 ) 4 3(1) 2 y 3( x 1) 2 7 Vertex : (-1,-7), a 3