Select the correct answer.

What is the domain and range of this function?

[tex]\[ f(x) = \log_5(x - 2) + 1 \][/tex]

A. domain: [tex]\(x \ \textgreater \ -2\)[/tex]; range: all positive real numbers
B. domain: [tex]\(x \ \textgreater \ 2\)[/tex]; range: all positive real numbers
C. domain: [tex]\(x \ \textgreater \ -2\)[/tex]; range: all real numbers
D. domain: [tex]\(x \ \textgreater \ 2\)[/tex]; range: all real numbers



Answer :

To determine the domain and range of the function [tex]\( f(x) = \log_5(x-2) + 1 \)[/tex], let's break down the problem step by step.

1. Determining the Domain:
- The logarithmic function [tex]\( \log_b(y) \)[/tex] is defined only for positive values of [tex]\( y \)[/tex]. This means that the argument of the logarithm, [tex]\( (x-2) \)[/tex], must be greater than 0.
- Therefore, the inequality we need to solve is:
[tex]\[ x - 2 > 0 \][/tex]
- Solving this inequality, we get:
[tex]\[ x > 2 \][/tex]
- Hence, the domain of [tex]\( f(x) \)[/tex] is [tex]\( x > 2 \)[/tex].

2. Determining the Range:
- The logarithmic function [tex]\( \log_5(y) \)[/tex] can produce any real number (positive, negative, or zero). When we add 1 to a real number, the result is still a real number.
- Therefore, the expression [tex]\( \log_5(x-2) + 1 \)[/tex] can take any real number value.
- Thus, the range of [tex]\( f(x) \)[/tex] is all real numbers.

Based on this information:

- The domain is [tex]\( x > 2 \)[/tex].
- The range is all real numbers.

The correct answer from the options provided is:

D. domain: [tex]\( x > 2 \)[/tex]; range: all real numbers