Math Problem Statement

Let 𝑓(π‘₯)=1π‘₯+2 and 𝑔(π‘₯)=π‘₯π‘₯βˆ’8 . Evaluate the following: 𝑔(𝑓(π‘₯))

Solution

We are tasked with evaluating g(f(x))g(f(x)), where the two given functions are:

f(x)=1x+2f(x) = \frac{1}{x} + 2 and g(x)=xxβˆ’8g(x) = \frac{x}{x - 8}

Step 1: Substitute f(x)f(x) into g(x)g(x)

We substitute f(x)=1x+2f(x) = \frac{1}{x} + 2 into the function g(x)g(x). This gives:

g(f(x))=f(x)f(x)βˆ’8g(f(x)) = \frac{f(x)}{f(x) - 8}

Substitute f(x)=1x+2f(x) = \frac{1}{x} + 2:

g(f(x))=1x+2(1x+2)βˆ’8g(f(x)) = \frac{\frac{1}{x} + 2}{\left(\frac{1}{x} + 2\right) - 8}

Step 2: Simplify the numerator and denominator

Now, simplify both the numerator and denominator.

  • Numerator: 1x+2\frac{1}{x} + 2 (This remains as it is).

  • Denominator: (1x+2)βˆ’8\left(\frac{1}{x} + 2\right) - 8. Simplify the constant part:

    2βˆ’8=βˆ’62 - 8 = -6

    So, the denominator becomes:

    1xβˆ’6\frac{1}{x} - 6

Step 3: Write the final expression

Now, substitute these simplified expressions into the equation:

g(f(x))=1x+21xβˆ’6g(f(x)) = \frac{\frac{1}{x} + 2}{\frac{1}{x} - 6}

This is the final expression for g(f(x))g(f(x)).

Would you like me to simplify this further or evaluate for specific values of xx?


Here are 5 related questions to expand your understanding:

  1. What happens when you evaluate g(f(x))g(f(x)) for a specific xx?
  2. How do you find the domain of the composite function g(f(x))g(f(x))?
  3. What would f(g(x))f(g(x)) look like in this case?
  4. How do vertical asymptotes change when combining two functions like this?
  5. What is the behavior of g(f(x))g(f(x)) as xx approaches infinity?

Tip: When composing functions, always check for potential restrictions on the domain based on both functions involved.

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Function Composition
Algebraic Fractions
Rational Functions

Formulas

f(x) = \frac{1}{x} + 2
g(x) = \frac{x}{x - 8}
g(f(x)) = \frac{f(x)}{f(x) - 8}

Theorems

Function Composition

Suitable Grade Level

Grades 10-12