Introduction to Mathematica's Solution of D.E.'s

 

Preliminaries.

 

Example 1. Use pencil and paper techniques and find the general solution to the D. E.
[Graphics:p1.txtgr1.gif].

 

Example 2. Use pencil and paper techniques and find the general solution to the I. V. P.
[Graphics:p1.txtgr2.gif].

 

Example 3. Use pencil and paper techniques and find the general solution to the I. V. P.
[Graphics:p1.txtgr3.gif].

 

Computer Lab Work.

First load Mathematica's Plot Vector Field subroutine.

[Graphics:p1.txtgr5.gif][Graphics:p1.txtgr4.gif]
 

Example 4. Use Mathematica to find the general solution to the D. E.
[Graphics:p1.txtgr6.gif].

[Graphics:p1.txtgr5.gif][Graphics:p1.txtgr7.gif]
 

Example 5. Use Mathematica to find the general solution to the I. V. P.
[Graphics:p1.txtgr8.gif].

[Graphics:p1.txtgr5.gif][Graphics:p1.txtgr9.gif]
 

Example 6. Use Mathematica to find the general solution to the I. V. P.
[Graphics:p1.txtgr10.gif].

[Graphics:p1.txtgr5.gif][Graphics:p1.txtgr11.gif]
 

Example 7. Use Mathematica's general solution and substitute values C = 0, 1, 2.
Plot the solutions over the interval [Graphics:p1.txtgr12.gif].

[Graphics:p1.txtgr5.gif][Graphics:p1.txtgr13.gif]

[Graphics:p1.txtgr5.gif][Graphics:p1.txtgr14.gif]

 

Example 8. Use Mathematica's general solution and make a table of functions
for the values C = -10, -9, ... , -2, -1, 0, 1, 2, ... ,10.
Plot the solutions over the interval [Graphics:p1.txtgr15.gif].

[Graphics:p1.txtgr5.gif][Graphics:p1.txtgr16.gif]

[Graphics:p1.txtgr5.gif][Graphics:p1.txtgr17.gif]

 

Example 9. Use Mathematica's Plot Vector Field subroutine and plot the vector slope field for the D. E.
[Graphics:p1.txtgr18.gif].

[Graphics:p1.txtgr5.gif][Graphics:p1.txtgr19.gif]

[Graphics:p1.txtgr5.gif][Graphics:p1.txtgr20.gif]

 

Example 10. Plot the solutions you found in 8 and the vector slope field in 9.

[Graphics:p1.txtgr5.gif][Graphics:p1.txtgr21.gif]

[Graphics:p1.txtgr5.gif][Graphics:p1.txtgr22.gif]

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

(c) John H. Mathews, 1998