To find the greatest common factor (GCF) of the expressions 4k, 18k^4, and 12, we first need to determine the factors of each term.
Step 1: Factor Each Term
- 4k: The factors are 4 and k, which can be broken down to 2 × 2 and includes the variable k.
- 18k^4: The factors are 18 and k4, which can be broken down to 2 × 3 × 3 and includes the variable k raised to the 4th power.
- 12: The factors are 12, which can be broken down to 2 × 2 × 3.
Step 2: Identify Common Factors
Next, we look for the common numerical factors among these terms:
- The prime factorization of 4k is 2^2 × k.
- The prime factorization of 18k^4 is 2 × 3^2 × k^4.
- The prime factorization of 12 is 2^2 × 3.
Step 3: Determine the Lowest Powers of Common Factors
The common prime factors are 2 and 3:
- For the number 2, the lowest exponent from the factorizations is from 18k^4, which is 21.
- For the number 3, the lowest exponent is from 12, which is 31.
- For the variable k, the lowest exponent is from 4k, which is k1.
Step 4: Calculate the GCF
The GCF is then calculated by multiplying the common factors with their lowest powers:
GCF = 21 × 31 × k1 = 2 × 3 × k = 6k
Conclusion
Therefore, the greatest common factor of 4k, 18k^4, and 12 is 6k.