(Complex Arithmetic)
(Complex Arithmetic)
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<math> (a + bi) * (c + di) = (ac - bd) + (ad + bc)i </math>
 
<math> (a + bi) * (c + di) = (ac - bd) + (ad + bc)i </math>
 +
 +
'''Division'''
 +
 +
<math> \frac{(a + bi)}{(c + di)} = \left({ac + bd \over c^2 + d^2}\right) + \left( {bc - ad \over c^2 + d^2} \right)i\ </math>

Revision as of 11:12, 5 September 2008

Notation

$ a+bi $ where a and b are real numbers, and i is the imaginary unit, which has the property $ i^2 = -1 $. The real number a is called the real part of the complex number, and the real number b is the imaginary part.

Complex Arithmetic

Addition and Subtraction

$ (a + bi) + (c + di) = (a + c) + (b + d)i $

$ (a + bi) - (c + di) = (a - c) + (b - d)i $

Multiplication

$ (a + bi) * (c + di) = (ac - bd) + (ad + bc)i $

Division

$ \frac{(a + bi)}{(c + di)} = \left({ac + bd \over c^2 + d^2}\right) + \left( {bc - ad \over c^2 + d^2} \right)i\ $

Alumni Liaison

To all math majors: "Mathematics is a wonderfully rich subject."

Dr. Paul Garrett