Greatest Common Factor

Definition

The greatest common factor (GCF) is the largest positive integer that divides each of the given integers without a remainder. It is an essential concept in number theory and is closely related to finding multiples, prime factorization, and factoring polynomials.

5 Must Know Facts For Your Next Test

1. The greatest common factor is used to simplify fractions by dividing both the numerator and denominator by the GCF.
2. Finding the GCF is an important step in solving linear equations with fractions and in reducing complex fractions to simplest form.
3. The GCF can be found using the prime factorization method, where you list the prime factors of each number and then select the common factors.
4. Knowing the GCF is essential for finding the least common multiple (LCM) of two or more numbers, as the LCM is the product of all the prime factors, taking the highest power of each.
5. Factoring polynomials often involves finding the GCF of the coefficients, which can help simplify the factorization process.

Review Questions

• Explain how the greatest common factor (GCF) is used to simplify fractions.
  • The greatest common factor is used to simplify fractions by dividing both the numerator and denominator by the GCF. This reduces the fraction to its simplest form by removing any common factors between the numerator and denominator. For example, if the fraction is 24/36, the GCF of 24 and 36 is 12. Dividing both the numerator and denominator by 12 gives the simplified fraction of 2/3.
• Describe the relationship between the greatest common factor (GCF) and the least common multiple (LCM) of two or more numbers.
  • The greatest common factor (GCF) and the least common multiple (LCM) of two or more numbers are inversely related. The GCF is the largest positive integer that divides each of the given integers without a remainder, while the LCM is the smallest positive integer that is divisible by all the given integers. The relationship between the GCF and LCM is that their product is equal to the product of the original numbers. This means that finding the GCF is an important step in determining the LCM, as the LCM is the product of all the prime factors, taking the highest power of each.
• Explain how the greatest common factor (GCF) is used in the process of factoring polynomials.
  • Finding the greatest common factor (GCF) of the coefficients in a polynomial is an essential step in the factorization process. By identifying the GCF, you can factor out a common factor from the entire polynomial, simplifying the factorization. This is particularly useful when factoring higher-degree polynomials, as the GCF can help identify common factors among the terms. Once the GCF is found, it can be factored out, leaving a simpler polynomial to factor further. Knowing how to efficiently find the GCF is a valuable skill in mastering polynomial factorization.

Related terms

Factors: Factors are the numbers that divide evenly into another number without a remainder.

Prime Factorization: Prime factorization is the process of expressing a number as a product of its prime factors.

Least Common Multiple (LCM): The least common multiple (LCM) is the smallest positive integer that is divisible by two or more given integers.