For questions 1 through 4, The functions \( p \) and \( r \) are shown. \[ p(x)=x^{2}-3 x+5 \quad r(x)=3 x-1 \] 1. Find a new function, \( c(x) \), that is defined by \( p(r(x)) \). 2. Determine the domain of \( c(x) \). Determine the range of \( c(x) \). Find \( p\left(r\left(\frac{1}{2}\right)\right) \).
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To find the new function \( c(x) \) defined by \( p(r(x)) \), we start by substituting \( r(x) \) into \( p(x) \). 1. **Finding \( c(x) \):** First, we need to substitute \( r(x) = 3x - 1 \) into \( p(x) = x^2 - 3x + 5 \): \[ c(x) = p(r(x)) = p(3x - 1) = (3x - 1)^2 - 3(3x - 1) + 5. \] Now, let's simplify \( c(x)\): \[ c(x) = (3x - 1)^2 - 9x + 3 + 5 = (9x^2 - 6x + 1) - 9x + 8 = 9x^2 - 15x + 9. \] 2. **Determining the domain of \( c(x) \):** The functions \( p(x) \) and \( r(x) \) are both polynomials, which are defined for all real numbers. Therefore, the domain of \( c(x) \) is: \[ \text{Domain of } c(x) = (-\infty, \infty). \] 3. **Determining the range of \( c(x) \):** To find the range of the quadratic function \( c(x) = 9x^2 - 15x + 9 \), we can use the vertex form. The vertex \( x \)-coordinate can be found using the formula \( x = -\frac{b}{2a} \): \[ x = -\frac{-15}{2 \cdot 9} = \frac{15}{18} = \frac{5}{6}. \] Now, substituting \( \frac{5}{6} \) into \( c(x) \): \[ c\left(\frac{5}{6}\right) = 9\left(\frac{5}{6}\right)^2 - 15\left(\frac{5}{6}\right) + 9 = 9 \cdot \frac{25}{36} - \frac{75}{6} + 9. \] This simplifies to: \[ = \frac{225}{36} - \frac{450}{36} + \frac{324}{36} = \frac{225 - 450 + 324}{36} = \frac{99}{36} = \frac{11}{4}. \] Since \( a = 9 > 0 \), the parabola opens upwards. Thus, the minimum value is \( \frac{11}{4} \) and the range is: \[ \text{Range of } c(x) = \left[\frac{11}{4}, \infty\right). \] 4. **Finding \( p\left(r\left(\frac{1}{2}\right)\right) \):** First, calculate \( r\left(\frac{1}{2}\right) \): \[ r\left(\frac{1}{2}\right) = 3 \cdot \frac{1}{2} - 1 = \frac{3}{2} - 1 = \frac{1}{2}. \] Now substitute this into \( p(x) \): \[ p\left(r\left(\frac{1}{2}\right)\right) = p\left(\frac{1}{2}\right) = \left(\frac{1}{2}\right)^2 - 3\left(\frac{1}{2}\right) + 5 = \frac{1}{4} - \frac{3}{2} + 5. \] Simplifying gives: \[ = \frac{1}{4} - \frac{6}{4} + \frac{20}{4} = \frac{1 - 6 + 20}{4} = \frac{15}{4}. \] In summary, we have: - \( c(x) = 9x^2 - 15x + 9 \) - Domain of \( c(x) = (-\infty, \infty) \) - Range of \( c(x) = \left[\frac{11}{4}, \infty\right) \) - \( p\left(r\left(\frac{1}{2}\right)\right) = \frac{15}{4} \)