29. , 30. ,
31. ,, 32. ,,
33. , 34. ,
35. , 36. ,
- ,,y 38. ,,x
- ,, 40. ,,
41.Concept Check Consider the following incorrectwork. WHAT WENT WRONG?
,or
42.One student added two rational expressions and obtained the answer. Another
student obtained the answer for the same problem. Both are correct. Explain.
Add or subtract as indicated. Write all answers in lowest terms. See Examples 3 – 6.
46. 47. 48.
49. 50. 51.
52. 53. 54.
3
x- 3
-
1
x
1
x- 1
-
1
x
5
t^4 u^7
-
3
t^5 u^9
+
6
t^10 u
1
a^3 b^2
-
2
a^4 b
+
3
a^5 b^7
4 t
9 a^8 b^7
+
5 s
27 a^4 b^3
2 r
7 p^3 q^4
+
3 s
14 p^4 q
5
12 x^5 y^2
+
5
18 x^4 y^5
4
15 a^4 b^5
+
3
20 a^2 b^6
7
18 a^3 b^2
-
2
9 ab
5
12 x^2 y
-
11
6 xy
5
x
+
9
4 x
8
t
+
7
3 t
3
5 - y
=
x- 4 x- 1
x+ 2
x
x+ 2
-
4 x- 1
x+ 2
2 x- 6 x^2 - x- 6 1 x+ 222 3 a- 3 b a^2 +ab- 2 b^21 a-b 22
2 y+ 6 y^2 - 9 9 x+ 18 x^2 - 4
2 t^2 + 7 t- 15 t^2 + 3 t- 10 s^2 - 3 s- 4 3 s^2 +s- 2
x^2 - 3 x- 4 x+x^2 y^2 - 8 y+ 12 y^2 - 6 y
m+n m-n m^2 - n^2 r+s r-s r^2 - s^2
x^2 - 81 x^2 + 18 x+ 81 y^2 - 16 y^2 - 8 y+ 16
378 CHAPTER 7 Rational Expressions and Functions
55. 56. 57.
58. 59. 60.
61. 62. 63.
64. 65. 66.
67. 68.
69. 70.
71. 72.
73. 74.
75. 76.
77. 78.
4 x+ 1
x+ 5
-
2
x
+
10
x^2 + 5 x
2 x+ 4
x+ 3
+
3
x
-
6
x^2 + 3 x
5
x+ 2
+
2
x^2 - 2 x+ 4
-
60
x^3 + 8
4
x+ 1
+
1
x^2 - x+ 1
-
12
x^3 + 1
5 x
x+ 3
+
x+ 2
x
-
6
x^2 + 3 x
3 x
x+ 1
+
4
x- 1
-
6
x^2 - 1
5 x
x- 3
+
2
x
+
6
x^2 - 3 x
5
x- 2
+
1
x
+
2
x^2 - 2 x
7
t- 2
-
6
t^2 - 2 t
-
3
t
15
y^2 + 3 y
+
2
y
+
5
y+ 3
4
x+ 3
-
x
x- 3
-
18
x^2 - 9
4 x
x- 1
-
2
x+ 1
-
4
x^2 - 1
- 2
x- 1
+
2
x+ 1
1
x+ 1
-
1
x- 1
a
a-b
-
b
b-a
w
w-z
-
z
z-w
3
2 - t
+
1
t- 2
2
4 - x
+
5
x- 4
13 x- 5
4 x- 1
-
x- 2
4 x- 1
11 x- 13
2 x- 3
-
3 x- 1
2 x- 3
7 x+ 8
3 x+ 2
-
x+ 4
3 x+ 2
17 y+ 3
9 y+ 7
-
2 x
x+ 4
+
3 x
x- 7
3 a
a+ 1
+
2 a
a- 3
