A.13.2: Section 13.2 Answers
( \newcommand{\kernel}{\mathrm{null}\,}\)
1. (ebxy′)′+cebxy=0
2. (xy′)′+(x−ν2x)y=0
3. (√1−x2y′)′+α2√1−x2y=0
4. (xby′)′+cxb−2y=0
5. (e−x2y′)′+2αe−x2y=0
6. (xe−xy′)′+αe−xy=0
7. ((1−x2)y′)′+α(α+1)y=0
9. λn=n2π2,yn=e−xsinnπx(n= positive integer)
10. λ0=−1,y0=1λn=n2π2,yn=e−x(nπcosnπx+sinnπx)(n= positive integer)
11.
- λ=0 is an eigenvalue y0=2−x
- none
- 5.0476821,14.9198790,29.7249673,49.4644528y=2√λcos√λx−sin√λx
12.
- λ=0 isn't an eigenvalue
- −0.5955245y=cosh√−λx
- 8.8511386,38.4741053,87.8245457,156.9126094y=cos√λx
13.
- λ=0 isn't an eigenvalue
- none
- 0.1470328,1.4852833,4.5761411,9.6059439y=√λcos√λx+sin√λx
14.
- λ=0 isn't an eigenvalue
- −0.1945921y=2√−λcosh√−λx−sinh√−λx
- 1.9323619,5.9318981,11.9317920,19.9317507y=2√λcos√λx−sin√λx
15.
- λ=0 isn't an eigenvalue
- −1.0664054y=cosh√−λx
- 1.5113188,8.8785880,21.2104662,38.4805610y=cos√λx
16.
- λ=0 isn't an eigenvalue
- −1.0239346y=√−λcosh√−λx−sinh√−λx
- 2.0565705,9.3927144,21.7169130,38.9842177y=√λcos√λx−sin√λx
17.
- λ=0 isn't an eigenvalue
- −0.4357577y=2√−λcosh√−λx−sinh√−λx
- 0.3171423,3.7055350,9.1970150,16.8760401y=2√λcos√λx−sin√λx
18.
- λ=0 isn't an eigenvalue
- −2.1790546,−9.0006633y=√−λcosh√−λx−3sinh√−λx
- 5.8453181,17.9260967,35.1038567,57.2659330y=√λcos√λx−3sin√λx
19.
- λ=0 is an eigenvalue y0=2−x
- −1.0273046y=2√−λcosh√−λx−sinh√−λx
- 8.8694608,16.5459202,26.4155505,38.4784094y=2√λcos√λx−sin√λx
20.
- λ=0 isn't an eigenvalue
- −7.9394171,−3.1542806y=2√−λcosh√−λx−5sinh√−λx
- 29.3617465,78.777456,147.8866417,236.7229622y=2√λcos√λx−5sin√λx
21. λ=0,y=xe−x20.1907286,118.8998692,296.5544121,553.1646458y=e−xsin√λx
22. λn=n2π2,yn=xsinnπ(x−2)(n= positive integer)
23. λ=0,y=x(2−x)20.1907286,118.8998692,296.5544121553.1646458,y=xsin√λ(x−2)
24. 3.3730893,23.1923372,62.6797232,121.8999231,200.8578309y=xsin√λ(x−1)
25.
- −L<δ<0
- δ=−L
26. λ0=−1α2y0=e−x/aλn=n2,yn=nαcosnx−sinnx,n=1,2,…
27.
- y=x−α
- y=αkcoshkx−sinkx
- y=αkcoskx−sinkx
29. b. λ=−α2/β2y=e−αx/β