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CANCAM '85: Proceedings, Tenth
Canadian Congress of Applied Mechanics, June 2-7, 1985, the University of Western Ontario, London, Ontario, Canada
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Chesser, H.; Rimrott, F.P.J. (1985). Rasmussen, H. (ed.). "Magnus
Triangle and Smelt Petal".
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524:{\displaystyle z=x^{3}-3xy^{2}=\operatorname {Re} =\operatorname {Re} =r^{3}\cos(3\varphi ).}
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may be used in contrast to monkey saddle, to designate an ordinary saddle surface in which
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https://www.researchgate.net/publication/256808897_Monkey_Starfish_and_Octopus_Saddles
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at the origin, while the curvature is strictly negative at all other points.
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would require two depressions for the legs and one for the tail. The point
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One can relate the rectangular and cylindrical equations using
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By replacing 3 in the cylindrical equation with any integer
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Peckham, S.D. (2011) Monkey, starfish and octopus saddles,
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16:Mathematical surface defined by z = x³ – 3xy²
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146:{\displaystyle z=\rho ^{3}\cos(3\varphi ).}
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83:{\displaystyle z=x^{3}-3xy^{2},\,}
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164:It belongs to the class of
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220:degenerate critical point
31:defined by the equation
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209:{\displaystyle (0,0,0)}
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21:mathematics
879:Categories
763:References
301:with zero
866:MathWorld
819:cite book
811:852789976
731:The term
547:≥
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27:is the
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93:or in
23:, the
825:link
807:OCLC
797:ISBN
721:= 0
719:xyz
501:cos
261:at
123:cos
19:In
881::
863:.
821:}}
817:{{
805:.
753:xy
717:+
713:+
709:+
653:z-
450:Re
410:Re
869:.
842:.
827:)
813:.
745:y
743:,
741:x
739:(
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715:z
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707:x
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680:1
677:,
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668:1
665:(
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633:=
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627:y
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621:+
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615:+
612:y
609:+
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577:k
553:,
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519:.
516:)
510:3
507:(
496:3
492:r
488:=
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477:i
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456:[
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431:y
428:i
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419:(
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407:=
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391:3
383:3
379:x
375:=
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350::
342:i
338:e
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331:=
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319:x
283:)
280:0
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274:0
271:(
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235:(
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204:)
201:0
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186:(
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138:)
132:3
129:(
118:3
110:=
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77:,
72:2
68:y
64:x
61:3
53:3
49:x
45:=
42:z
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