Name _____________________________________ Date ________________________
LESSON 1.6
Practice B
Solve the equation
1. x2 = 36
2. x2 + 121 = 0
3. x2 + 9 = 4
4. x2 = 2 x2 + 4
5. 3 x2 + 40 = x2  56
6. 11x2 =  x2  1
7. (x  3)2 =  12
8. 2(x  1)2 = 36
9. 4(x  2)2 + 320 = 0
Write the expression as a complex number in standard form.
10. (1 + i) + (3 + i)
11. (4  3i) + (2 + 6i)
12. (4  i)  (4 + 5i)
13. (5  3i) + (3  6i)
14. 3i(4 + 2i)
15. 2i(3  i)
16. (2 + i)(4 + 2i)
17. (5  2i)(1  3i)
18.  (3 + i)(7  3i)
19. 2i(1 + i)(2 + 3i)
20. (2  i)2
21. (5 + 3i)(5  3i)
5
22.
3  2i

23. 2 i
3  4i

24. 1 2i
2 i
25. 3 (3  2i )
2  4i
Find the absolute value of the complex number.
26. 3 4i
27. 1  i 3
5  2i 2
28.
Plot the numbers in a complex plane.
29. 3i
30. 2 + 2i
31. 2  3i
Using the properties of exponents, write the complex number in standard form.
32. 2 + i2
33. 3 + i3
34. 5  i4
35. 2  i5
36. 1 + i4
37. 1 + i8
38. 1 + i12
39. 1 + i16
40. Pattern Recognition Using the information from Exercises 3639, write a general statement about the
value of in where n is a positive factor of 4. Use this statement to write 2 + i207 in standard form.
Answer Key
Lesson 1.6
Practice Level B
1. ± 6i
2. ± 11i
3.  i 5
4. ± 2i
5.  2 i 6
6. 
1
i
4
7. 3  2 i 3
8. 1  3 i 2
 2  4i 5
9.
10. 4 + 2i
11. 6 +3i
12. – 8 – 6i
13. 2 – 9i
14. – 6 + 12i
15. – 2 – 6i
16. 6 + 8i
17. – 1 – 17i
18. –24 + 2i
19. 10 + 2i
20. 3 – 4i
21. 34
22.
23.
24.
15

13
10
2

11
25
25
2
2
25. 
i
13
i
2 2 1

3
27
10
26. 5
27. 2
28. 13
29.
30.
31.
32. 1
33. 3 – i
3

7
5
i
i
34. 4
35. 2 – i
36. 2
37. 2
38. 2
39. 2
40. If the exponent of i is a factor of 4 the expression can be reduced to 1. To simplify i raised to any natural
number, factor out the multiples of 4 in the exponent and simplify the remaining expression;
  
2  i 207  2  i 204 i 3  2  i 3  2  i