Precalculus

Answers Section 2.5 A-1145. a.b. B(t) 10t 2 60t 2700Total production is virtually constant.Maximum: 2790Minimum: 2700b. g(n) 113 1 (assuming a hot dog and bun weigh one fourth4 nof a pound)c. ( f o g)(t) 2524 t 282525; (g o f )(t) 6 24 t 113d. (g o f )(t) represents Kobayashi’s weight after t minutes.47. False 49. FalseSection 2.4, page 1781. Inverses 3. Not inverses5. Inverses 7. Inverses9. Inverses 11. 1–113. Not 1–1 15. 1–117. Not 1–1 19. Not 1–121. 1–1; f 1 (x) 3x 323. Not 1–125. 1–1; f 1 (x) x 1, x 1127. 1–1; f 1 (x) (x 2 5), x 0 29. Not 1–1231. 1–1;x f 1 (x)33. Not 1–135.Production25002000150010005001 2 3 4 5 6 7f(t) 25 t, 0 t 1264 07 110 213 316 4f 1 5y = ƒ(x) 4 y = ƒ –1 (x)37. does not exist.321–5 –4 –3 –2 –1 1 2 3 4 5–2–3–4–5yB(t)xMonth39.41. a. M(t) 98 0.12t b. 110°F c. M 1 (t) 8.33t 817d. M 1 (t) gives the year (after 1935) in which the maximum temperatureis t°F. For example, since M 1 (120) 183, this modelpredicts that the maximum temperature will be 120°F in 2117.43. a. 4 yearsb. f 1 (t) 72 approximates the interest rate at which an amountttakes t years to double.c. 9%45. a. Yes; the formula suggests a maximal weight of 195 pounds.b. Assume h 0; f 1 (w) 5.30548w gives the maximumheight required for a person of a given weight to not be overweight.16 1 254321–5 –4 –3 –2 –1 1 2 3 4 5–2–3–4–5c. About feet tall d. Answers may vary.47. False 49. TrueSection 2.5, page 1921. Quadratic 3. None 5. None 7. Linear9. Linear 11. Piecewise13.y54321 f(x) = 2x – 1x–5 –4 –3 –2 –1 1 2 3 4 5–2–3–4–5Slope 2; y-intercept 115.y5432h(x) = – 3x 14+ 4x–5 –4 –3 –2 –1 1 2 3 4 5–2–3–4–5yy = ƒ –1 (x)y = ƒ(x)xSlope 3 ; y-intercept 14