final project

chapter 7 notes

book report

Hey everyone, this is what I got. Email me all your criticism. Bryan

Note, I'm using t for t_0, and c for omega_0.

click here to get the Mathematica notebook file


In[1]:=

t = Integrate[Sqrt[x/(c + (1 - c) x)], {x, 0, 1}]

Out[1]=

If[c/(-1 + c) 0, (2 (1 - c)^(1/2) + (-1 + 1/c^(1/2) c^(1/2)) c Log[4] - 2 c Log[1 + (1 ...  - c)^(3/2)), Integrate[x/(c + x - c x)^(1/2), {x, 0, 1}, Assumptionsc/(-1 + c) ≠0]]

Despite what the If statement says, I think the first expression is what we want when 0<c<1.  I think we can make a few other simplifications, also.  It comes out to the function below.

In[2]:=

Plot[1/(1 - c) + (c Log[c^(1/2)/(1 + (1 - c)^(1/2))])/(1 - c)^(3/2), {c, 0, 1}, PlotRange-> {0, 1}, AxesLabel {"c", "t"}] ;

[Graphics:HTMLFiles/index_4.gif]

The graph fits the two points we knew beforehand (c,t) = (1, 2/3) and (c,t) = (0, 1).  Also, t does increase as c decreases.

In[3]:=

FindRoot[1/(1 - c) + (c Log[c^(1/2)/(1 + (1 - c)^(1/2))])/(1 - c)^(3/2) == .87 , {c, .5}]

Out[3]=

RowBox[{{, RowBox[{c, , 0.149709}], }}]

So when c > .1497, t > .87.  That wasn't too bad.


Created by Mathematica  (October 26, 2003)