Directions: Using the digits 1 to 9, fill in the boxes to produce a logarithm that meets the indicated requirements. Each digit can only be used once.

1. [tex]\log _{\square} \square[/tex]
- Produces an integer

2. [tex]\log _{\square} \frac{\square}{\square}[/tex]
- Produces an irrational number

3. [tex]\log _{\square} \square^{\square}[/tex]
- Produces a rational number



Answer :

Alright, let's solve this problem step-by-step:

### Condition 1: Produces an integer

We need to fill in the boxes to make the expression:
[tex]\[ \log_{\square} \square \quad \text{produce an integer} \][/tex]
The logarithm of a number [tex]\( b \)[/tex] with base [tex]\( a \)[/tex] [tex]\(( \log_a b )\)[/tex] produces an integer if [tex]\( b \)[/tex] is an integer power of [tex]\( a \)[/tex]. So, we need to find [tex]\( a \)[/tex] and [tex]\( b \)[/tex] such that:
[tex]\[ \log_a b = n \quad \text{where} \quad n \in \mathbb{Z} \][/tex]
For example:
[tex]\[ \log_2 8 = \log_2 2^3 = 3 \][/tex]
So, one possible solution is:
[tex]\[ a=2 \quad \text{and} \quad b=8 \][/tex]

### Condition 2: Produces an irrational number

We need to fill in the boxes to make the expression:
[tex]\[ \log_{\square} \frac{\square}{\square} \quad \text{produce an irrational number} \][/tex]
A logarithm is irrational when the base [tex]\( a \)[/tex] and the argument [tex]\( b \)[/tex] are such that [tex]\( b \)[/tex] is not an integer power of [tex]\( a \)[/tex], and they do not have a simple fractional or exponential relationship.

For instance:
[tex]\[ \log_3 2 \][/tex]
This is irrational because 2 is not an integer power of 3 nor does it have a straightforward fractional or exponential relationship with 3.

### Condition 3: Produces a rational number

We need to fill in the boxes to make the expression:
[tex]\[ \log_{\square} \square^{\square} \quad \text{produce a rational number} \][/tex]
A logarithm of the form [tex]\(\log_a (b^c)\)[/tex] produces a rational number if [tex]\(b^c\)[/tex] is a power of [tex]\(a\)[/tex].

For example:
[tex]\[ \log_3 (3^2) = 2 \quad \text{and} \quad \log_2 (4^3) = 6 \][/tex]

Putting it all together, a possible set of digits from 1 to 9 that meet these criteria are:

### Possible Solutions

1. Integer Logarithm:
[tex]\[ \log_2 8 \quad \text{which simplifies to} \quad 3 \quad (\text{an integer}) \][/tex]

2. Irrational Logarithm:
[tex]\[ \log_3 \frac{2}{1} \quad \text{which simplifies to} \quad \log_3 2 \quad (\text{irrational}) \][/tex]

3. Rational Logarithm:
[tex]\[ \log_3 3^2 \quad \text{which simplifies to} \quad 2 \quad (\text{rational}) \][/tex]

So, the filled-in logs with these conditions might look like:

[tex]\[ \log_2 8 \quad \text{produces an integer,} \][/tex]
[tex]\[ \log_3 \frac{2}{1} \quad \text{produces an irrational number,} \][/tex]
[tex]\[ \log_3 3^2 \quad \text{produces a rational number.} \][/tex]

These satisfy all the given conditions using the digits 1 to 9 exactly once.