Which function has the greater estimated average rate of change over the interval [0,1.1] , the exponential function y=4x or the quadratic function y=4x2 ? Option 1: exponential function Option 2: quadratic function

1 answer

To determine which function has the greater estimated average rate of change over the interval \([0, 1.1]\), we can calculate the average rate of change for both functions over this interval.

  1. Exponential function: \( y = 4x \)

    The average rate of change of the function from \( x = a \) to \( x = b \) is given by: \[ \text{Average Rate of Change} = \frac{f(b) - f(a)}{b - a} \] For \( y = 4x \), we calculate:

    • \( f(0) = 4 \cdot 0 = 0 \)
    • \( f(1.1) = 4 \cdot 1.1 = 4.4 \)

    Now we can compute the average rate of change: \[ \text{Average Rate of Change}_{\text{exponential}} = \frac{f(1.1) - f(0)}{1.1 - 0} = \frac{4.4 - 0}{1.1 - 0} = \frac{4.4}{1.1} = 4 \]

  2. Quadratic function: \( y = 4x^2 \)

    Similarly, we calculate for the quadratic function:

    • \( g(0) = 4 \cdot 0^2 = 0 \)
    • \( g(1.1) = 4 \cdot (1.1)^2 = 4 \cdot 1.21 = 4.84 \)

    Now we compute the average rate of change: \[ \text{Average Rate of Change}_{\text{quadratic}} = \frac{g(1.1) - g(0)}{1.1 - 0} = \frac{4.84 - 0}{1.1 - 0} = \frac{4.84}{1.1} \approx 4.4 \]

Now we compare the results:

  • The exponential function has an average rate of change of \( 4 \).
  • The quadratic function has an average rate of change of approximately \( 4.4 \).

Since \( 4.4 > 4 \), we can conclude that:

Option 2: quadratic function has the greater estimated average rate of change over the interval \([0, 1.1]\).