Cool math fractal

math image

math image

pre-algebra help lessonsalgebra help lessonsprecalculus / calculus help lessonsmath anxiety survival guidegeometry math artmath and jigsaw puzzlesCoolmath booksother math stuff
math help lessonsmath practice problemsmath gamesmath dictionarygeometry trigonometry reference area
teacher's areaparent's areaCoolmath 4 kidsSpike's Game ZoneFinance FREAKTotally Stressed OutScience Monster
Coolmath Algebra
Complex Numbers Lesson 2 - Factoring the Sum of Two Squares
(page 1 of 2)
---- This algebra lesson explains how to factor the sum of two squares.

math image
Now available: Coolmath Algebra books! Part 1, Part 2 and Part 3 covering the Algebra you need from Algebra 1 through Precalculus Algebra (Beginning Algebra through College Algebra)

other Coolmath Books: Coolmath Precalculus Review (the math you really need to survive Calculus 1) and Math Survival Guide (How to conquer math and deal with math anxiety)
line
Graphing Calculator Scientific Calculator << a new window will open for these
line
Remember the difference of two squares?

We can factor this guy:

x^2 - 9 = ( x - 3 ) ( x + 3 )

You've probably been told that you couldn't factor this guy...

x^2 + 9
The SUM of two squares.

Well, they fibbed...  You CAN factor this guy...  Just not with real numbers.

We just need one more thing though:

Since   

  i = sqrt( -1 )

Squaring both sides gives

i^2 = -1

So, check this out:

I claim that

x^2 + 9 factors as ( x - 3i ) ( x + 3i )
Just like the difference of two squares...  but with i's after the numbers.

Continued on the next page

 The printing and distribution and/or downloading of these lessons is strictly prohibited.
line
Graphing Calculator Scientific Calculator << a new window will open for these
line

.....:::::::::::::::  HELP SUPPORT COOLMATH  :::::::::::::::.....
:::::::  link to us   :::::::   advertise with us  :::::::  why we have ads  :::::::

Thanks for visiting Coolmath.com
© 1997-2010 Coolmath.com, Inc.