92 REFERENCES
(i) Introducing a potential function where
D
x
C h.x/; u D
t
x
; (4.149)
shows that the shallow water equations become
2
x
tt
2
t
x
tx
C
2
t
g
3
x
xx
gh
0
.x/u
3
x
D 0: (4.150)
(ii) Show that under a modified Hodograph transformation, this equation for h.x/ D
˛x can be transformed to
U
3
X
U
T T
gU
XX
D 0: (4.151)
Further show that under a Legendre transformation, this equation can be linearized.
Compose the two transformations.
4.5 REFERENCES
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