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Task 4: Solutions

As accurately as you can, determine a2, a3 etc, and a¥. And determine e1, e2 etc. Calculate the dn. Do they converge to about 4.67? The ratio ei /ei+1 should converge to about 2.50.

After a¥ the diagram is quite confusing up until close to 4, where the population sequence is consistently chaotic. [Note the white bands. Can you explain what is happening for theses values of a? Also note the dark lines. Any ideas what might cause them? Can you detect aas what might cause them? Can you detect any patterns in the oscillations?]

This task is simplified with the use of this applet, created by Jarrod Pickens:

Here are values obtained by using the applet:

a1 = 3
a2 = 3.4494
a3 = 3.5441
a4 = 3.5644
a5 = 3.56875
a6 = 3.5697
a¥ = 3.5699



e1 = 0.406
e2 = 0.157
e3 = 0.062
e4 = 0.0247
e5 = 0.00987



The values above give estimates of 4.66 for d and 2.51 for e.

The white bands represent areas of periodic behavior even after a¥. Looking carefully one can find cycles of period 6 and period 5. The dark lines show `favored' cycle points. These are the limit points of the sequences (f2n (x1)), (f3n(x1)) etc.



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