It is when you add 1+1 to get 2 then you do 2+2 to get 4 and then do 4+4 to get 8 and so on.
http://wiki.answers.com/Q/What_are_doubles_fact_in...

Double Angle, or Double Number Identities are Trig identities that show how to find
http://www.chacha.com/question/whatisadoublesf...

1. Use simple manipulatives or household objects to enable children to see why basic math facts are true. Show two blocks in one pile and three blocks in another. Push the two piles
http://www.ehow.com/how_4842137_teachmathfacts.h...

1. Choose a proper place and time to start learning these facts without being interrupted. Ad. 2. Get comfortable so you can be focus only in what ever you are learning. 3. Develop
http://www.wikihow.com/MemorizeMathFacts
