To find the average rate of change of the height function \( h(t) = -16t^2 + 160t \) over the interval \([4, 5]\), we can use the formula for average rate of change:
\[ \text{Average rate of change} = \frac{h(b) - h(a)}{b - a} \]
where \( a = 4 \) and \( b = 5 \).
First, we need to calculate \( h(4) \) and \( h(5) \):
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Calculate \( h(4) \): \[ h(4) = -16(4^2) + 160(4) \] \[ = -16(16) + 640 \] \[ = -256 + 640 \] \[ = 384 \text{ feet} \]
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Calculate \( h(5) \): \[ h(5) = -16(5^2) + 160(5) \] \[ = -16(25) + 800 \] \[ = -400 + 800 \] \[ = 400 \text{ feet} \]
Now we can use these values to find the average rate of change over the interval \([4, 5]\):
\[ \text{Average rate of change} = \frac{h(5) - h(4)}{5 - 4} \] \[ = \frac{400 - 384}{5 - 4} \] \[ = \frac{16}{1} \] \[ = 16 \text{ feet per second} \]
Thus, the average rate of change of the rocket over the interval \([4, 5]\) is 16 feet per second.