Factor is the concept that one polynomial can be divisible by another polynomial. For example, the polynomial a+b can be divisible by the polynomial (A 2-AB+B 2), so (A 2-AB+B 2) is a factor of (a+b).

The concept of factor is very important in algebra. When a polynomial is divisible by another polynomial, the latter is a factor of the former. The use of factors can help us simplify and understand complex polynomial expressions. In factor calculation, there are many methods to choose from, such as common factor method, formula method, group decomposition method and the application of factor decomposition. These methods can help us to decompose polynomials, so as to better understand and deal with mathematical problems. Factorization is the process of decomposing a polynomial into simpler order products, which is widely used in algebra, such as solving equations, simplifying expressions and finding the roots of polynomials.