Answer :

elcharly64

Answer:

Proof below

Step-by-step explanation:

Irrational and Rational Numbers

We need to use the basic property of logarithms:

[tex]log_b\ a=x\ \ \Rightarrow b^x=a[/tex]

We are given:

[tex]log_3\ 7[/tex]

And we will prove it's an irrational number, i.e., it's not a rational number.

Recall a rational number can always be expressed as a fraction a/b, where a and b are integer numbers. Thus, if the expression was a rational number, then:

[tex]\displaystyle log_3\ 7=\frac{a}{b}[/tex]

Applying the property:

[tex]\displaystyle 3^{\frac{a}{b}}=7[/tex]

Raising to the power of b:

[tex]3^a=7^b[/tex]

It's not possible to find two integers a and b that satisfy the condition above. That contradiction comes from the assumption that [tex]log_3\ 7[/tex] is rational, thus, it's proven [tex]log_3\ 7[/tex] is irrational.

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