1.3 Complex Numbers

Complex Number = a + bi a is the Real part b is the Imaginary partIf b = 0, then a + bi = aIf a = 0, and b does not equal 0, the Complex Number is a Pure Imaginary Number, eg. 3iIf a does not equal 0 and b does not equal 0, it is a Non-real Complex Number, eg. 1 + 6iA Complex Number written in the form a + bi or a + ib

Important Words Complex Number Real Part Imaginary Part Pure Imaginary Number Nonreal Complex Number Standard Form Complex Conjugate

What is i? i is an Imaginary NumberIt represents the square root of -1i squared = -1

Using i in operations Use square root of -a = i(square root of a) before anything elseAdd or subtract Real Parts and add or subtract Imaginary PartsFOIL when multiplying(a + bi)(a - bi) are Complex Conjugates. To divide 2 Complex Numbers multiply both the numerator and the denominator by the complex conjugate of the denominator