Chapter CSB1.3, Problem 19E

To determine

To find: the LCM of monomials $7x,12x$ .

Answer to Problem 19E

The LCM of numbers is $84x$ .

Explanation of Solution

Given:

The monomials are $7x$ and $12x$ .

Calculation:

LCM means least common multiple. Least common multiple of two numbers or monomials (say a and b ) is the smallest positive number or monomial which is divisible by either the numbers or monomials ( b and a ).

Factorize each monomial as follows:

  $\begin{array}{c}7x=7^1\times x^1\\ 12x=2^1\times 2^1\times 3^1\times x^1\end{array}$

LCM of the numbers is,

  $\text{LCM}=2^1\times 2^1\times 3^1\times 7^1\times x^1=84x$

Thus, the LCM of numbers is $84x$ .