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Alg 2 Unit 8AB Quiz v.1 Name: Per Target 8A: I can evaluate & graph exponential growth & decay. _ . /10 1. Graph the following functions. Include at least 3 accurate points. a) y = (2.5)* b) f ( x ) = e-2x 2. State whether the following functions represent exponential growth or decay. . Patty had a headache and took 200mg of Tylenol. Her body eliminates 18% of the Tylenol every hour. a) f(x) = (1.25)* b ) f ( x ) = ( 5 ) c ) y = e 0.5x d) y = 3e-2x She wanted to calculate how much of the medicine would be left after 4 hours, so she used the function y = 200(1.18)4. a) What, if anything, did Patty do wrong in her calculation? b) What is the amount of Tylenol that will remain in her system after 4 hours? Target 8B: I can model with exponential functions_ 3. A credit card company is offering a rate of 8% interest on purchases but compounds interest continuously. If you purchase a TV for $800 with your credit card and don't make any payments, how much will you owe at the end of 2 years? Write an equation and solve. OPTIONAL Target 7A Retake: I can perform operations and find domain. -/10 1 . f ( x ) = 2xz and g(x) = 8xz a) Find (fg) (x). b) What is the domain of (fg)(x)? c) Find () (x). d) What is the domain of () (x)? 2. f(x) = 12V2x - 1 and g(x) = -3V2x - 1 a ) Find (f + g ) (x ) . b) What is the domain of (f + g) (x)? c) Find (f - 9)(x) d) Evaluate ( f - 9)