1. 1.3 Multiply & Divide Complex Numbers

2. Remember Typo! See p. 12 First, remember = _____,
so what would = _____
So… What is… _______
__________
Typo! See p. 12

3. Multiply 2 Complex Numbers
BUT!!!! Bewaaaare of i2!!!!
Distribute or…
FOIL (just like w/ real numbers & variables)
1) )
3) 4) -1

4. Guided Practice #1-3, p. 11

5. Hey, did you know? Complex Conjugates
a + bi and a – bi have names for each other…
Ex: 5 + 3i and… ______
-2i and… ______
-4 – 2i and… ______
Complex Conjugates

6. Multiplying Complex Conjugates
REAL
ALWAYS RESULTS IN A ________ NUMBER.
(5 + 3i) ( ) =
-2i ( ) =
(-4 – 2i)( ) =

7. Dividing Complex Numbers
Just like radicals we can not have complex numbers in the denominator of a fraction.
Remember, we can multiply any fraction by a factor of “1,” and it will not change the fraction.
If a complex number or just an imaginary number is in the denominator we will multiply numerator and denominator by the complex conjugate
DISTRIBUTE OR FOIL depending on what you have

8. Divide 2 Complex Numbers
Write the expression as a complex number in standard form.

9. More Practice

10. Homework
Pg. 13, 1 – 35 odds