1. 11.4 Roots of Complex Numbers
To find roots of complex numbers.

2. Roots of a complex number
In general, a non zero complex number will have two square roots, three cube roots, four fourth roots, and k kth roots.
The number 1 has 3 cube roots, one real and two imaginary, which can be found by solving x3-1=0. De Moivre’s theorem provides another method for finding the cube roots of 1.
What does this mean??????

3. Find the cube roots of 8i
We can check our solutions using De’ Moivre’s Th.

4. Nth Roots of a Complex Number
Lets use the previous example and apply this analysis.

5. Find the fourth root of -16

6. Example
Find the three cube roots of -1.

7. Example Find the square roots of
Plot and its square roots on an Argand diagram.

8. Homework
Section 11.4
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