College

9. Which of the following pairs are like terms?

A. [tex]7x^2[/tex] and [tex]1x^3[/tex]
B. [tex]3x[/tex] and [tex]3x^3[/tex]
C. [tex]4x^3[/tex] and [tex]2x^3[/tex]
D. [tex]2x^4[/tex] and 2

Answer :

To determine whether two terms are like terms, we must check if they have the same variable raised to the same power. Let's analyze each pair:

1. For the first pair, consider the terms
[tex]$$7x^2 \quad\text{and}\quad 1x^3.$$[/tex]
Although both contain the variable [tex]$x$[/tex], the exponents are [tex]$2$[/tex] and [tex]$3$[/tex], respectively. Since the exponents are different, these are not like terms.

2. For the second pair, consider the terms
[tex]$$3x \quad\text{and}\quad 3x^3.$$[/tex]
Here, [tex]$3x$[/tex] can be thought of as [tex]$3x^1$[/tex]. Comparing the exponents [tex]$1$[/tex] and [tex]$3$[/tex], they are not the same, so these terms are not like terms.

3. For the third pair, consider the terms
[tex]$$4x^3 \quad\text{and}\quad 2x^3.$$[/tex]
Both terms have the variable [tex]$x$[/tex] raised to the same exponent, [tex]$3$[/tex]. Therefore, these terms are like terms.

4. For the fourth pair, consider the terms
[tex]$$2x^4 \quad\text{and}\quad 2.$$[/tex]
The constant term [tex]$2$[/tex] can be considered as [tex]$2x^0$[/tex] (since any number is equivalent to the number times [tex]$x^0$[/tex]). Comparing the exponents [tex]$4$[/tex] and [tex]$0$[/tex], they are different. Hence, these are not like terms.

In conclusion, among the given pairs, only the third pair ([tex]$4x^3$[/tex] and [tex]$2x^3$[/tex]) are like terms.

Final Answer: Only pair 3 represents like terms.