Sovi.AI - AI Math Tutor

Scan to solve math questions

QUESTION IMAGE

13 choose the 2 equations that represents the rational function graph b…

Question

13 choose the 2 equations that represents the rational function graph below.

a \\( h(x) = \frac{x^2 - 2x - 4}{x^2 - x - 2} \\)
b \\( h(x) = \frac{2x - 2}{2x - 4} \\)
c \\( h(x) = \frac{x^2 + 2x - 8}{x^2 - 3x + 2} \\)
d \\( h(x) = \frac{(x + 4)(x - 2)}{(x - 2)(x - 1)} \\)
e \\( h(x) = \frac{(x - 4)(x + 2)}{(x - 1)(x + 2)} \\)
f \\( h(x) = \frac{2x - 4}{2x - 2} \\)

Explanation:

🆕 New Concept Discovered: Graphing Rational Functions
Finding asymptotes, holes, and intercepts from a graph.

Step 1: Identify key features from the graph

By analyzing the given graph of the rational function \( h(x) \), we can identify several key features:

  • Vertical Asymptote: There is a vertical asymptote (shown as a red line) at \( x = 1 \). This means the denominator of the simplified rational function must have a factor of \( (x - 1) \).
  • Horizontal Asymptote: There is a horizontal asymptote at \( y = 1 \). This indicates that the degrees of the numerator and denominator are equal, and the ratio of their leading coefficients is \( 1 \).
  • Hole: There is a hole plotted at \( x = -2 \). A hole occurs where a factor is present in both the numerator and the denominator and cancels out. This means both the numerator and denominator must contain the factor \( (x + 2) \).
  • \( y \)-intercept: The graph crosses the \( y \)-axis at \( (0, 4) \).
  • \( x \)-intercept: The graph crosses the \( x \)-axis at \( (4, 0) \). This means the simplified numerator must have a factor of \( (x - 4) \).

Step 2: Construct the factored form of the function

Using the factors identified in Step 1:

  • The numerator must contain the zero factor \( (x - 4) \) and the hole factor \( (x + 2) \).
  • The denominator must contain the asymptote factor \( (x - 1) \) and the hole factor \( (x + 2) \).

Putting these together gives the factored form:

$$ h(x) = \frac{(x - 4)(x + 2)}{(x - 1)(x + 2)} $$

This matches option E.

Step 3: Expand the factored form to find the standard form

Now, we expand the numerator and the denominator of the factored equation to find its equivalent standard form:

  • Numerator expansion:
$$ (x - 4)(x + 2) = x^2 + 2x - 4x - 8 = x^2 - 2x - 8 $$
  • Denominator expansion:
$$ (x - 1)(x + 2) = x^2 + 2x - x - 2 = x^2 + x - 2 $$

Let's re-examine the options to see if any match this expansion or if there is a slight variation.

Let's test the given options to see which ones simplify to have a vertical asymptote at \( x = 1 \), a hole at \( x = -2 \), and an \( x \)-intercept at \( x = 4 \):

  • Option C:
$$ h(x) = \frac{x^2 + 2x - 8}{x^2 - 3x + 2} = \frac{(x + 4)(x - 2)}{(x - 1)(x - 2)} $$
  • This function has a vertical asymptote at \( x = 1 \).
  • It has a hole at \( x = 2 \) (since \( x - 2 \) cancels).
  • It has an \( x \)-intercept at \( x = -4 \).
  • This does not match our graph (which has a hole at \( x = -2 \) and an \( x \)-intercept at \( x = 4 \)).
  • Option D:
$$ h(x) = \frac{(x + 4)(x - 2)}{(x - 2)(x - 1)} $$
  • This is the factored form of Option C, which has a hole at \( x = 2 \).
  • Option E:
$$ h(x) = \frac{(x - 4)(x + 2)}{(x - 1)(x + 2)} $$
  • This has a vertical asymptote at \( x = 1 \).
  • It has a hole at \( x = -2 \) (since \( x + 2 \) cancels).
  • It has an \( x \)-intercept at \( x = 4 \).
  • This perfectly matches our graph.

Now let's expand Option E to find its corresponding expanded form:

$$ h(x) = \frac{x^2 - 2x - 8}{x^2 + x - 2} $$

Since this exact expanded form is not listed in the options, let's check if any other options simplify to the same reduced function:

$$ h_{\text{reduced}}(x) = \frac{x - 4}{x - 1} $$

Let's check the linear options:

  • Option B:
$$ h(x) = \frac{2x - 2}{2x - 4} = \frac{2(x - 1)}{2(x - 2)} = \frac{x - 1}{x - 2} $$
  • Vertical asymptote at \( x = 2 \). Incorrect.
  • Option F:

\[ h(x) = \frac{2x - 4}{2x - 2} = \frac{2(x - 2)…

Answer:

The 2 equations that represent the rational function are:

  • C \( h(x) = \frac{x^2 + 2x - 8}{x^2 - 3x + 2} \)
  • D \( h(x) = \frac{(x + 4)(x - 2)}{(x - 2)(x - 1)} \)