Compare the estimated average rate of change of the exponential function y=9(13)x

and the quadratic function y=9x2+13x
. Which function has a negative estimated average rate of change over the interval [0.1,0.6]
?(1 point)
Responses

the quadratic function
the quadratic function

the exponential function
the exponential function

both functions
both functions

neither function

1 answer

To find the estimated average rate of change for each function over the interval \([0.1, 0.6]\), we can use the formula for average rate of change:

\[ \text{Average Rate of Change} = \frac{f(b) - f(a)}{b - a} \]

where \(f(x)\) is the function, and \(a = 0.1\) and \(b = 0.6\).

For the exponential function: \(y = 9(13^x)\)

  1. Calculate \(f(0.1)\): \[ f(0.1) = 9(13^{0.1}) \approx 9(1.347) \approx 12.123 \]

  2. Calculate \(f(0.6)\): \[ f(0.6) = 9(13^{0.6}) \approx 9(5.395) \approx 48.555 \]

  3. Calculate the average rate of change: \[ \text{Average Rate of Change} = \frac{48.555 - 12.123}{0.6 - 0.1} = \frac{36.432}{0.5} = 72.864 \]

For the quadratic function: \(y = 9x^2 + 13x\)

  1. Calculate \(f(0.1)\): \[ f(0.1) = 9(0.1^2) + 13(0.1) = 9(0.01) + 1.3 = 0.09 + 1.3 = 1.39 \]

  2. Calculate \(f(0.6)\): \[ f(0.6) = 9(0.6^2) + 13(0.6) = 9(0.36) + 7.8 = 3.24 + 7.8 = 11.04 \]

  3. Calculate the average rate of change: \[ \text{Average Rate of Change} = \frac{11.04 - 1.39}{0.6 - 0.1} = \frac{9.65}{0.5} = 19.3 \]

Comparison of rates of change:

  • Average rate of change of the exponential function = \(72.864\)
  • Average rate of change of the quadratic function = \(19.3\)

Both rates of change are positive. Therefore, the conclusion is:

Response: neither function.