Technical Mathematics, Sixth Edition

D.9. CHAPTER 9

Exercise 1

1. (2, −1)

3. (1, 2)

5. (−0.24, 0.90)

7. (3, 5)

9.

11. (−3, 3)

13. (1, 2)

15. (3, 2)

17. (15, 6)

19. (3, 4)

21. (2, 3)

23. (−3, 5)

25. (1.63, 0.0970)

27. m = 2, n = 3 29. w = 6, z = 1

31. (9.36, 4.69)

33. v = 1.06, w = 2.58

Exercise 2

1. (a) 9.85mi/h (b) 4.27 mi/h

3. 5.3 mi/h and 1.3 mi/h

5. $2500 at 4%

7. $2684 at 6.2% and $1716 at 9.7%

9. $ 6000 for 2 years

11. 2740 lb mixture; 271 lb sand

13. 5.57 lb peat; 11.6 lb vermiculite

15. T₁ = 490 lb; T₂ = 185 lb

17. Carpenter: 25.0 days; helper: 37.5 days

19. 18,000 gal/h and 12,000 gal/h

21. 92,700 people and 162,000 people

23. l₁ = 13.1 mA; l₂ = 22.4 mA

25. R₁ = 27.6 Ω; α = 0.00511

27. h = 352 ft; d = 899 ft

29. v₀ = 0.381 cm/s; a = 3.62 cm/s²

Exercise 3

1. (60, 36)

3. (87/7, 108/7)

5. (15, 12)

7. m = 4, n = 3

9. r = 3.77, s = 1.23

11. (1/2, 1/3)

Exercise 4

1. (15, 20, 25)

3. (1, 2, 3)

5. (5, 6, 7)

7. (1, 2, 3)

9. (3, 4, 5)

11. a = −3, b = 4, c = −3/2

13. (3, 6, 9)

15. (2, −1, 5)

17. (3a, 2a, a)

19. (c, c, ab/c)

21. 2/3A, 7/3A, 2/3A

23. F₁ = 9890 lb, F₂ = 9860 lb, F₃ = 9360 lb

Review Problems

1. (3, 5)

3. (5, −2)

5. (2, −1, 1)

7.

9. (8, 10)

11. (2, 3)

13. [(a + b − c)/2, (a − b + c)/2, (b − a + c)/2]

15. (7, 5) 17. (1, −5, −4)

19. (2, 3, 1)

21. (13, 17)

23. $450 ...