What are the vertical asymptotes and holes in the graph of the function y = (3x + 1)(x – 1)/(x + 5)?

To analyze the function y = \frac{(3x + 1)(x – 1)}{(x + 5)} for vertical asymptotes and holes, we need to examine both the numerator and the denominator.

Step 1: Identify the Holes

Holes occur in the graph of a function where both the numerator and the denominator are equal to zero at the same value of x. First, let’s find the roots of the numerator:

  • Set the numerator to zero: (3x + 1)(x – 1) = 0
  • This gives us two factors: 3x + 1 = 0 and x – 1 = 0
  • Solving these equations, we find:
    • x = -\frac{1}{3} (from 3x + 1)
    • x = 1 (from x – 1)

Next, we check the denominator:

  • Set the denominator to zero: x + 5 = 0
  • Solving this gives us: x = -5

Since neither values (-1/3 and 1) derived from the numerator are the same as the denominator’s root (x = -5), there are no holes in the graph.

Step 2: Identify the Vertical Asymptotes

Vertical asymptotes occur at values of x that make the denominator equal to zero while the numerator is not equal to zero. In this case, we can determine the vertical asymptote by solving:

  • Set the denominator to zero: x + 5 = 0
  • This leads to x = -5

Now, we check if the numerator is not zero at this value:

  • Substituting x = -5 into the numerator gives us: (3(-5) + 1)(-5 – 1) = (-15 + 1)(-6) = -14(-6) = 84

Since the numerator is non-zero at x = -5, we confirm there is a vertical asymptote at:

x = -5

Conclusion

In summary:

  • No holes in the graph.
  • A vertical asymptote exists at x = -5.

This understanding of vertical asymptotes and holes will aid in sketching and analyzing the behavior of the function near these critical points!

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