(2) Find vertical and horizontal asymptotes of the following functions. Show your work. Evaluate all the necessary limits. (i) \( f(x)=\frac{2 x-1}{3 x^{2}+5 x-2} \) (ii) \( f(x)=\frac{-x^{3}+2 x^{2}}{x^{4}-4 x^{3}+4 x^{2}} \)
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To find the vertical and horizontal asymptotes of the given functions, we will evaluate limits and identify points of discontinuity. **(i) \( f(x)=\frac{2 x-1}{3 x^{2}+5 x-2} \)** 1. **Vertical Asymptotes:** Vertical asymptotes occur where the denominator is equal to zero and the numerator is not zero at those points. We need to set the denominator to zero: \[ 3x^2 + 5x - 2 = 0 \] Factoring or using the quadratic formula: \[ x = \frac{-5 \pm \sqrt{(5)^2 - 4(3)(-2)}}{2(3)} = \frac{-5 \pm \sqrt{25 + 24}}{6} = \frac{-5 \pm 7}{6} \] This yields: \[ x = \frac{1}{3} \quad \text{and} \quad x = -2 \] Thus, vertical asymptotes are at \( x = \frac{1}{3} \) and \( x = -2 \). 2. **Horizontal Asymptotes:** For rational functions, the horizontal asymptotes depend on the degrees of the polynomial in the numerator and denominator. Here, the degree of the numerator (1) is less than the degree of the denominator (2). Therefore: \[ y = 0 \quad \text{(the x-axis)} \] This means there is a horizontal asymptote at \( y = 0 \). --- **(ii) \( f(x) = \frac{-x^{3} + 2x^{2}}{x^{4} - 4x^{3} + 4x^{2}} \)** 1. **Vertical Asymptotes:** To find vertical asymptotes, we set the denominator to zero: \[ x^{4} - 4x^{3} + 4x^{2} = 0 \implies x^{2}(x^{2} - 4x + 4) = 0 \] This gives: \[ x^2 = 0 \quad \text{or} \quad (x - 2)^2 = 0 \] Thus, we have a vertical asymptote at \( x = 0 \) and a repeated root at \( x = 2 \), indicating a vertical asymptote at \( x=2 \). 2. **Horizontal Asymptotes:** The degree of the numerator (3) is less than the degree of the denominator (4). Therefore, there is a horizontal asymptote at: \[ y = 0 \] So, for this function, there is also a horizontal asymptote at \( y = 0 \). To summarize, the vertical asymptotes for the first function are at \( x = \frac{1}{3} \) and \( x = -2 \) with a horizontal asymptote at \( y = 0 \). The second function has vertical asymptotes at \( x = 0 \) and \( x = 2 \), with a horizontal asymptote at \( y = 0 \).