Banach Fixed Point and Differential Equations

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ChemEng1
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Homework Statement


Find the value of x, correct to three decimal places for which: [itex]\int^{x}_{0}\frac{t^{2}}{1+t^{2}}dt=\frac{1}{2}[/itex].

Homework Equations


Banach's Fixed Point Theorem
Picard's Theorem?

The Attempt at a Solution


I'm not sure where to start with this type of problem.

From other BFPT problems, I will need to show a contraction mapping into itself.

Any pointers would be greatly appreciated.
 
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Banach's fixed point theorem and Picard's method show that this problem has a unique solution. Actually finding the solution doesn't require that.

You could, for example, actually integrate that:
[tex]\int_0^x \frac{t^2}{1+ t^2}dt= \int_0^x 1- \frac{1}{t^2+ 1}dt[/itex] <br /> is pretty easy to integrate.[/tex]
 
[itex]\int^{x}_{0}\frac{t^{2}}{1+t^{2}}dt=\int^{x}_{0}(1-\frac{1}{1+t^{2}})dt[/itex]

Let t=tanθ. Then dt=sec2θdθ.

[itex]\int^{x}_{0}(1-\frac{1}{1+t^{2}})dt=\int^{x}_{0}dt-\int^{x}_{0}\frac{1}{sec^{2}\vartheta}[/itex]sec2θdθ=[itex]\int^{x}_{0}dt-\int^{x}_{0}[/itex]dθ=t-arctan(t) from 0 to x=x-arctan(x).

x-arctan(x)=.5 at x=1.4743.

Are you familiar with any approaches that use BFPT?
 
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