THIRD EDITION ULT1VAR1ABLE 1VI IVlATHElVIATlCS Richard E. Williamson • Hale E. Trotter MULTIVARIABLE MATHEMATICS MULTIVARIABLE MATHEMATICS THIRD EDITION RICHARD E. WILLIAMSON DartmouthCollege HALE TROTTER F. PrincetonUniversity PRENTICEHALL,UpperSaddleRiver, NewJersey07458 LibraryofCongressCataloging-in-PublicationData Williamson,RichardE. — Multivariablemathematics/RichardE.Williamson.HaleF.Trotter. 3rded. p. cm. Includesindex. ISBN0-13-181645-4(hardcover) 1.Algebras,Linear. 2.Differentialequations. 3.Calculus. I.Trotter,HaleF. II. Title. QA184.W54 1996 512'.15—dc20 95-36238 AcquisitionEditor:GeorgeLobell ProductionEditor:ElaineWetterau CoverDirector:JayneConte ManufacturingBuyer:AlanFischer ProjectManagement:MonotypeEditorialServices CompositionandPre-press:MonotypeCompositionCompany _^^^^H^ S©1i9m9o6n,&19S7c9h,ubsytePrr/eAntViicea-cHoalml,CoInmcp.any * UpperSaddleRiver,NewJersey07458 Allrightsreserved.Nopartofthisbook maybereproducedinanyformor byanymeanswithoutpermissioninwriting fromthepublisher. PrintedintheUnitedStatesofAmerica 10 9 8 7 6 5 4 3 2 I ISBN D-l3-lfilb^s-^ PrenticeHallInternational(UK)Limited,London PrenticeHallofAustraliaPty.Limited,Sydney PrenticeHallCanadaInc.,Toronto PrenticeHallHispanoamericana.S.A.,Mexico PrenticeHallofIndiaPrivateLimited,NewDelhi PrenticeHallofJapan,Inc.,Tokyo Simon&SchusterAsiaPte.Ltd.,Singapore EditoraPrenticeHalldoBrasil,Ltda.,RiodeJaneiro 1 Contents PREFACE CHAPTER 1 VECTORS 1 CoordinateVectors 1 2 GeometricVectors 8 A Pointsandvectors,8 B Distanceandlength, 1 C Scalarmultiplication, 12 D Vectoraddition, 13 E Points,arrows,andvectors, 16 3 LinesandPlanes 19 A Lines, 19 B Planes,22 CHAPTER2 DOTPRODUCTSANDCROSSPRODUCTS 28 1 DotProducts 28 A Lengthandangle,28 B Unitvectorsandprojections,30 C Propertiesofx-yandIxl,34 vi Contents 2 EuclideanGeometry 37 A Equationsforlinesandplanes,38 B Distancetoalinein31^oraplanein3P,39 C Thecrossproductin31^,42 CHAPTER3 EQUATIONSANDMATRICES 49 1 SystemsofLinearEquations 49 2 SolvingLinearEquations 55 A Coefficientmatricesandelementaryoperations,55 B Reducedmatrices,61 3 MatrixAlgebra 65 A Sumandscalarmultiple,65 B Matrixmultiplication,66 C Identitymatrices,69 4 InverseMatrices 73 A Invertibility, 73 B Computinginverses, 74 C Specialmatrices, 77 5 Determinants 80 A Definition,80 B Rowandcolumnexpansions,82 C Basicproperties,83 D Computingdeterminants,86 E Invertiblematrices,87 CHAPTER4 DERIVATIVES 93 1 FunctionsofOneVariable 94 A Derivatives,94 B Velocityandspeed,99 C Higher-orderderivatives, 100 D Arclength, 101 E Computerplottingofspacecurves, 105 F Vectorintegration, 106 2 SeveralIndependentVariables 112 A Graphofafunction, 112 B Levelsets, 113 C Computer-generatedgraphs, 115 D Quadricsurfaces, 116