MATH 5383
You are given an ordinary differential equation 3/'(t) = f(t,y), tela, b), where f(t, y) and fy(t, y) are continuous and bounded in the vertical...
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# Trying to complete the 1st question on this page. I have no idea where to start the process of even beginning the

question.

You are given an ordinary differential equation
3/'(t) = f(t,y), tela, b), where
f(t, y) and fy(t, y) are continuous and bounded in the vertical strip D = [a, b] x IR.
Given a number I, you are to find a E IR so that the solution to the IVP,
y'(t) = f(t, y), te [a, b], y(a) = a, satisfies
L.&quot; u(t) at = 1.
Just to be clear: you are given a &lt; b E R, a subroutine that will evaluate f(t, y) for
(t, y) ED, and I E R. From this, you are to explain how to find a E R. You may
assume such a exists and is unique.
You can invent a new method or use methods we have discussed in class. Your
algorithm should be clear, but does not need the detail of source code. You may
assume the reader knows all of the methods we have discussed in class, so don't
describe any of them in detail.
You will be graded mostly on your discussion of why you selected the method(s) that
you did. Discuss possible sources of errors and when we might expect them to be
large. Analyze the algorithm to estimate which steps will use the most computational
resources (function evaluations and/ or memory). There are many different answers to
this problem that would get full credit.
Hint: Since y depends on a, one could write y = y(t; a), and you may want to
consider a function like g(a) = 1 - fa y(t; a) dt.
2. Theorem 5.10 (inequality 5.13) of our text gives an upper bound on the error from
Euler's method to (IVP) using the step size h and a bound, , on the rounding errors.
Assume you know a = 0, M = 4 and L = 3. Take o ~ 10-13 and do ~ 2 * 10-16 as
your o values. Using all of these values, find a value of h which minimizes the upper
bound on the absolute error given in the theorem at t = b. Now using this value of h,
and for each of b = 1, b = 2, 6 =4, and b = 8, give the upper bound for the error at
t =b, the number of time steps N, and the number of function evaluations needed.
Now in an attempt to model an RK4 method, replace the factor (by + ; ) (from the
theorem referenced above) with (Sh,M + &quot; ), find a new optimal h, and redo your error
bounds, time steps, and function evaluations as above. Discuss your results briefly.

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