1540470959-Boundary_Value_Problems_and_Partial_Differential_Equations__Powers

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Chapter 7 493


Chapter 7 Miscellaneous Exercises



  1. ui+^1 −( ^2 uxi) 2 +ui−^1 −



24 xiui=0,i= 0 , 1 ,2,
u 1 −u− 1
2 x =1,u^3 =1;

− 18 u 0 + 18 u 1 = 6 ,
9 u 0 − 20. 83 u 1 + 9 u 2 = 0 ,
9 u 1 − 22 u 2 =− 9 ,

u 0 =− 0 .248,u 1 = 0 .08,u 2 = 0 .44.

3.

ui+ 1 − 2 ui+ui− 1
( x)^2 +

1

1 +xi

ui+ 1 −ui− 1
2 x =−(^1 +xi),
i= 1 , 2 , 3 ;u 0 = 1 ,u 4 =0;

− 32 u 1 + 17. 60 u 2 =− 15. 65 ,
14. 67 u 1 − 32 u 2 + 17. 33 u 3 =− 1. 5 ,
14. 86 u 2 − 32 u 3 =− 1. 75 ,

u 1 = 0 .822,u 2 = 0 .606,u 3 = 0 .335.
5.ui(m+ 1 )=(ui− 1 (m)+ui+ 1 (m))/2. Note that u 3 (m)=u 1 (m)and
u 4 (m)=u 0 (m).

i
m 01 2
0 00 0
10.030 0
2 0.06 0.015 0
3 0.09 0.03 0.15
4 0.12 0.053 0.03
5 0.14 0.075 0.053
6 0.17 0.1 0.075
7 0.20 0.122 0.10
8 0.22 0.15 0.122


  1. First problem:ui(m+ 1 )=(ui+ 1 (m)+ui(m)+ui− 1 (m))/3; second prob-
    lem:ui(m+ 1 )=(ui+ 1 (m)+ui− 1 (m))/3.

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