1.6 Operations on Functions and Composition of Functions • Pg. 73 Pg. 67 # 132 – 137 # 8 – 18 even, 43 – 46 all, 67 • A school club buys a scientific calculator for $18.25 to use as a raffle prize. The club charges $0.50/ticket. – – – – Write an equation of the club’s profit. Graph your equation. Find the domain and range. How many tickets must be sold to realize a profit? 1.6 Operations on Functions and Composition of Functions Pg. 66 Problems • #13 • #15 fog D: [-1, ∞ ) R: [-2, ∞ ) gof D: (- ∞ , -1]U[1, ∞ ) R: [0, ∞) • #17 fog D: [-2, ∞ ) R: [-3, ∞ ) gof D: (- ∞ , -1]U[1, ∞ ) R: [0, ∞) fog D: (-∞, 1)U(1, ∞ ) R: (-1, ∞) gof D: (- ∞ , -√2)U (-√2, √2)U(√2, ∞ ) R: (- ∞, 0)U(0, ∞) #39 – 42 • #39 – same graph shifted up one • #40 – same graph shifted down 2 • #41 – graph stretched by 2 • #42 – graph reflected about the x – axis and then stretched 2 1.6 Operations on Functions and Composition of Functions Composition Effects on Transformations and Reflections • Depending on what you are composing, you could just be creating a shift or reflection of a function. • Look at what is inside the f◦g(x) to see if anything could transpire before you would consider graphing the new function. Balloon Fun!! • A spherically shaped balloon is being inflated so that the radius r is changing at the constant rate of 2 in./sec. Assume that r = 0 at time t = 0. Find an algebraic representation V(t) for the volume as a function of t and determine the volume of the balloon after 5 seconds. 1.6 Operations on Functions and Composition of Functions Shadow Movement • Anita is 5 ft tall and walks at the rate of 4 ft/sec away from a street light with it’s lamp 12 ft above ground level. Find an algebraic representation for the length of Anita’s shadow as a function of time t, and find the length of the shadow after 7 sec. More Rectangles!! • The initial dimensions of a rectangle are 3 by 4 cm, and the length and width of the rectangle are increasing at the rate of 1 cm/sec. How long will it take for the area to be at least 10 times its initial size? 2.1 Zeros of Polynomial Functions Polynomial Functions • What is a polynomial function? • What is a zero? • How can you tell the max number of zeros from a polynomial function? Find the zeros… • Algebraically: – – – x2 – 18 = 0 (x – 2)(2x + 3) = 0 |x – 4| = 10 • Using your calculator: – – – x3 – 2x2 + x – 1 = 0 x2 + 5x = 4 3x3 – 25x + 8 = 0