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masterred
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Homework Statement
a. Use algebra and calculus to find the positive fixed point p(c) (in terms of c) and identify its exact interval of stability.
b. Use algebra and calculus to find the exact interval of stability of this fixed point
c. Use algebra to find the point p1(c), p2(c) of the 2-cycle (in terms of c), and identify its exact interval of stability.
d. Use algebra and calculus to find the exact interval of stability of this 2-cycle.
Homework Equations
fc(x) = 4/x + x/2 - c for 0<c<2.3
The Attempt at a Solution
I did part a and solved that 4/x + x/2 - c = x and got -c + sqrt(c^2+8).
For part b I was supposed to take the derivative of 4/x + x/2 - c which I got to be -4/x^2 + 1/2. I was then supposed to replace x with -c+sqrt(c^2+8) and make it into an inequality -1<-4/(-c+sqrt(c^2+8))<1 and solve and I broke it up and found c<1 (not sure if this is correct).
For part c I was supposed to solve 4/(4/x + x/2 -c) + .5(4/x + x/2 -c) = x and I got -12c^2x^2 - 4cx^3 + 64cx + 3x^4 - 16x^2 - 64. I was then supposed to divide x-(-c+sqrt(c^2+8) into that problem via long division and I keep trying but I am never to find the exact solution.