question 1'
the height, h centimeters, of water in a rive above its normal level at a time, t days, after a thunderstorm is given by
h= 3t^2 - t^3 0
a) find dh/dt
b)find the rate of change, in centimeters per day, of the height of water in the river after 2.5 days.
c) find the values of t for which the height of water is increasing.
question2'
the size of a population, P, of birds on an island is modelled by p=59 + 117t + 57t^2 - t^3 where t is the time in years after 1970.
a)find dp/dt
b) i) find the positive value of t for which P has stationary value.
ii) determine whether this stationary value is a maximum or minimum
c) i) state the year when the model predicts that the population will reach its maximum value.
ii) determine what the model predicts will happen in the year 2029.
2007-06-05
07:04:58
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1 answers
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asked by
Paige M
1
in
Mathematics