Download Basic Functions and Their Graphs

Complex Numbers
Section 2.1
Objectives
• Rewrite the square root of a negative
number as a complex number.
• Write the complex conjugate of a
complex number.
• Add, subtract, multiply, and divide two
complex numbers.
• Solve a quadratic equation with complex
solutions.
Vocabulary
• complex number
• complex conjugate
Rewrite the following square
root so that there is no longer
a negative sign under the
square root symbol.
4
Rewrite the following square
root so that there is no longer
a negative sign under the
square root symbol.
 36
Rewrite the following square
root so that there is no longer
a negative sign under the
square root symbol.
5
Evaluate the expression
3  2i   6  4i 
Evaluate the expression
5  5i    8  2i 
Multiply the following two
numbers together.
 2  i 3  7i 
Find the complex conjugate of
each of the following:
3  2i
2 i
5i
1 i
5
Multiply the following two
numbers together.
3  2i 3  2i 
Evaluate the expression
3  2i 
4  5i 
Solve the equation:
x 90
2
Solve the equation:
x  4x  5  0
2
Solve the equation:
2x  3  2x
2