carrying capacity problem

Biologists stocked a lake with 400 fish and estimated the carrying capacity (the maximal population for the fish of that species in that lake) to be 7000 . The number of fish doubled in the first year. dP/dt = rP(1- p/K) find an expression for the size of the population after t years by determining constant r.

Logistic model

A population obeys the logistic model. It satisfies the equation : dP/dt = 2/1300 P(13-P) for P>0 Find when P is increasing and decreasing.

carrying capacity

Suppose that a population develops according to the logistic equation: dP/dt = 0.15P - 0.003P^2 where t is measured in weeks. what is the carrying capacity?

Logistic model

A population obeys the logistic model. It satisfies the equation dP/dt = 2/1300 P(13-P) for P>0 Assume P(0)= 3 Find P(74)

Elementary Differentail equations college coarse homework

Please view attached zip file. Contains jpeg images of homework problems. There are 7 pages, please view them in 100 % size to see them correctly. This is a homework assignment for an elemnatary diffeq college coarse. ANSWERS ARE PROVIDED but you need to solve them step by step and SHOW all these steps, and if possible explain ...continues

Second order linear

Find y as a function of t if 25y'' + 40y'+52y= 0 y(0)=1 y'(0)=6

Second order linear diff. equation

Find y as a fucntion of t if 25y'' +81y=0 y(0)=3 y'(0)=6

second order diff. eq.

find y as a function of t in y''- y = 0 y(0)=9 y(1)=2

2nd order diff. eq

4y'' + 30y=0 find y as a function of t y(0)=5 y'(0)=7

second order diff eq

find y as a function of t for: 64y'' + 64y' + 18y=0 y(0) = 4 y'(0) = 4