If you don't mind I will experiment with your post using the "math" tag:

mikau wrote:

Yeah, always remember the differance of two squares.

.Always be on the look out for numbers with integer square roots. For instance

.Also variables with even exponants other (then zero) can always be converted to a square.

Example of the first one:

`[math]\Large x^2 - y^2 = (x + y)(x - y)[/math]`

Now, using the math tag makes things a *little* slower, so best to use when other options fail. I often just cut and paste the symbols from the top of the forum, but there is no "^4", so that is where the math tag could help.

]]>Hmm... x[sup]2[\sup]

]]>if you want to factor x^2+4 you have to use Ruffini, or interpret this as (x^2 - y^2). The y in this case would be √-4=j√4:

(x^2-(√-4)^2) = (x + √-4 )*(x - √-4 ) = (x + j√4)*(x - j√4), j indicates it is an imaginary number (j = √-1).

nu

]]>(X^2 + 4)

Now I can't think of a way how to factor it.

]]>I know it can be done.

]]>