C H A P T E R 2 Polynomial and Rational Functions

77.
79.
4 2 4 2 3i 2 1 i
2 3i 1 i 2 3i 2 3i 1 i 1 i
3x 2 1
x 2 1
3
8 12i
4 9
8
13
x ± 1
3
12
i 1 i
13
8
13 1 12
i i 13
21 1
13 13 i
± 1
i ±3
3 3 i
2 2i
1 1
3x 2 1 0 80.
78.
Review Exercises for Chapter 2 247
1 5 1 4i 52 i
2 i 1 4i 2 i1 4i
2 8x 2 0
8x 2 2
x 2 1
4
x ± 1
2 i
81. x2 2x 10 0 82. 6x2 3x 27 0
83.
87.
89.
x 2 2x 1 10 1
x 1 2 9
x 1 ±9
x 1 ± 3i
f x 3xx 2 2 84.
Zeros: x 0, x 2
f x x 4x 6x 2ix 2i
Zeros: x 4, x 6, x 2i, x 2i
Possible rational zeros:
f x x 4x 9 2 85.
Zeros: x 9, 4
± 1
±1, ±3, ±5, ±15, ±
3 5 15
4 , ± 4 , ± 4 , ± 4
1 3 5 15
2 , ± 2 , ± 2 , ± 2 ,
88.
x b ± b2 4ac
2a
3 ± 639
12
3 ± 3i71
12
1 4i 10 5i
2 8i i 4i 2
9 i 2 9i
2 9i 2 9i
18 81i 2i 9i2
4 81i 2
9 83i
85
3 ± 32 4627
26
x 1x 8
Zeros: x 1, x 8
9 83i
85 85
1 71
±
4 4 i
f x x 2 9x 8 86.
Zeros: x 5, 8, 3 ± i
f x x 3 6x
xx 2 6
Zeros: x 0, ±6i
f x x 8x 5 2 x 3 ix 3 i
fx 4x3 8x2 3x 15 90. fx 3x4 4x3 5x2 8
Possible rational zeros: ± 1 2 4 8
±1, ±2, ±4, ±8, 3 , ± 3 , ± 3 , ± 3