LESSON 1 – MAXIMA AND MINIMA (COMPLETING THE SQUARE) STANDARD FORM 2 𝑦 = 𝑎𝑥 + 𝑏𝑥 + 𝑐 𝑎 is the stretch or compression factor. 𝑐 is the initial value COMPLETING THE SQUARE VERTEX FORM 𝑦 = 𝑎(𝑥 − ℎ)2 + 𝑘 𝑎 is the stretch or compression factor. (ℎ, 𝑘) is the vertex PERFECT SQUARE TRINOMIALS Example ① Example ② Expand a) (𝑥 + 5)2 Factor the following perfect square trinomials a) 𝑥 2 + 6𝑥 + 9 b) 𝑥 2 − 2𝑥 + 1 Completing the Square: 𝑏 2 𝑐= ( ) 2 Example ③ b) (𝑥 − 3)2 Adding a constant to a quadratic expression to form a perfect square trinomial. Determine the missing number to create a perfect square trinomial. a) 𝑥 2 + 8𝑥 + _____ b) 𝑥 2 − 14𝑥 + _____ c) 𝑥 2 + 1.4𝑥 + _____ d) 𝑥 2 − 2 𝑥 + _____ 5 Example ① Determine the vertex of each quadratic relation by completing the square. State the vertex, axis of symmetry, the maximum or minimum value and the values y may take. a) 𝑦 = 𝑥 2 – 8𝑥 + 4 1 𝑎=1 Write the value of 𝑏 = ________ Divide b by 2 and square the result 𝑏 2 2 (2) = ______ Add and subtract the value from 1 3 Factor the first three terms (it will be a perfect square trinomial) 1 Factor 𝑎 from the first and second terms ONLY. 2 Write the NEW value of 𝑏 = ________ Divide b by 2 and square the result b) 𝑦 = −2𝑥 2 + 8𝑥 + 3 a≠1 𝑏 2 (2) = ______ c) 𝑦 + 3 = 𝑥 2 + 4𝑥 3 Add and subtract the value from 1 4 Multiply the last term by ‘a’ 5 Factor the three terms inside the brackets it will be a perfect square trinomial) d) 𝑦 = −6𝑥 + 3𝑥 2