Factorizing an expressionYou know that , that is to say, . Factorizing is starting from and writing .
You can also factorize some expressions using the third remarkable identity, "the other way round" :
It is also a factorization as the result is a product.
Product equationsProduct equations are equations of the type
If the product of two numbers is equal to 0, then at least one of the two numbers is equal to 0. If , then a = 0 or b = 0 (or both). In tests, you have to know how to write the following sentence : "A product of 2 factors is equal to 0 if one of the 2 factors is equal to 0". Hence, when you have , you write the sentence, then :
(the author of the website apologizes if « or » is not exactly aside the operations).
Problem : solve
It’s a product equation. The product of factors is equal to 0 if and only if one of its factors is equal to 0. Hence:
See also : algebra on fmaths.com