1. Imaginary Numbers
4.6 Solve by finding Square Roots
(with Complex Numbers)

2. Evaluate
9

3. A new kind of number…
 Evaluate the square root of a negative number
 Imaginary number –
1i  

4. Evaluate
9
1 9 
9i
3i
3i

5. Evaluate
18
1 18 
18i
9 2i 
3 2i

6. Solve the equation
2
25x  
2
25x   
25x i 
5x i 

7. Solve the equation
2
52x  
2
52x   
52x i 
2 13x i 

8. Solve the equation
2
17 5x  
2
12x   
12x i 
2 3x i 
2
12x  

9. Solve the equation
2
3 5 40x   
2
15x   
15x i 
2
3 45x  
2
15x  

10. Solve the equation
 
2
6 3 42x  
 
2
3 7x    
3 7x i  
 
2
3 7x   
3 7x i  

11. Complex Number
 Complex means: Consisting of more than one
type of “thing”
 Therefore, a “complex number”, is a number that
consists of more than one type of number, a real
number portion and an imaginary number portion.
a bi

12. An interesting fact…
 Complex numbers occur in pairs, called
“Complex Conjugates”
a bi a bi
5 3i 5 3i
2 6i  2 6i 

13. Assignment
p. 279 # 3 - 11