Serving as a basic introduction to concepts in deterministic biological modeling, this text shows how relatively simple mathematics can be applied to a variety of models to draw interesting conclusions.
Consider the difference equation xn+2 3 xn+1+2 xn=0.
Show that the general solution to this equation is
Now suppose that x0 10 and x1=20. Then A1 and A2 must satisfy the system of equations
Solve for A1 and A2 and find the solution to the above initial valueproblem.
2.
Solve the following difference equations subject to the specified x values and sketch the solutions:
xn?5 xn?1+6 xn ?2=0; x0=2, x1=5.
xn+1 5 xn+4 xn?1=0; x1=9, x2=33.
xn?xn?2=0; x1=3, x2=5.
xn+22 xn+1=0; x0=10.
xn+2+ xn+1 2 xn=0; x0=6, x1=3.
xn+1=3 xn; x1=12.
3.
[*]In Section 1.3 it was shown that the general solution to equations (16a,b) is (22) provided ?1??2. Show that if ?1= ?2= ? then the general solution is
Solve and graph the solutions to each of the following equations or systems
xn+2?xn=0,
xn+22 xn+1+
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