How to determine the LCM to allow us to add two rational expressions

The video tutorial discusses the concepts of the greatest common factor (GCF) and least common multiple (LCM), explaining how to determine the smallest number that two expressions divide into. It covers the rules of exponents and division, correcting common mistakes in calculations. The tutorial concludes with a final calculation, emphasizing the importance of understanding mathematical principles and processes.

What is the least common multiple (LCM) of 4 and 5?

• 25

• 20

• 15

• 10

Which of the following is true about the division of exponents?

• You add the powers when dividing.

• You multiply the powers when dividing.

• You subtract the powers when dividing.

• You divide the powers when dividing.

What is the result of multiplying 4X by 5X?

• 20X

• 20X^2

• 9X

• 9X^2

How do you find a common denominator for the expressions 5/20X^3 and 4X^2/20X^3?

• Add the numerators directly

• Use 20X^3 as the common denominator

• Multiply both by 4X^2

• Multiply both by 5

What is the final simplified form of the expression 4X^2 + 5 divided by 20X^3?

• 5 / 20X^3

• 4X^2 + 5 / 20X^3

• 4X^2 / 20X^3

• 4X^2 + 5