SECTION 6.5
32.
38.
!
4!
!
5!
2
7!
!3"
5"
2
!
3"
2
!"
!2"
11!
2
42. (a) amp = 3, per = π,
phase shift = – π/4
"
!%
y
=
3sin
$
2x
+
'
(b)
#
2&
44. (a) amp = 3, per = 1,
phase shift = – 1/4
!%
"$
'
y
=
3
sin
2
!
x
+
(b)
#
2&
"$ ! %'
I
=
510
sin
t
46.
# 12 &
52.
14
101
192.25
–22
52.(b) January 11, (t = 9.75 ≈ 10)
54. a = 5, b = π/12, c = – π, d = 15
SECTION 6.7
0
2. ! = 45 , a = 35, c = 35 2
0
4. ! = 30 , a = 3 3 , b = 3
0
0
6. ! = 60 , ! = 30 , b = 4
0
0
8. ! = 45 , ! = 45 , a = 7 2
0
10. ! = 25 40' , b ≈ 41.8, c ≈ 46.4
0
12. ! = 58 50' , b ≈ 843, c ≈ 985
0
0
14. ! " 74 , ! " 16 , c ≈ 32
0
0
16. ! " 38 , ! " 52 , b ≈ 0.53
18. b = csin !
20. a = b tan!
15
26. ≈ 6.1 meters
SECTION 6.7
32. ≈ 5.76 minutes
34. ≈ 108.1 feet
44. ≈ 45.5°
46. (a) ≈ 7.49 feet, (b) ≈ 1.51 feet
48. ≈ 30.1 meters
50. ≈ 22.6 feet