数学专业英语(吴炯圻-第2版)2-2

NewWords&Expressions:angle角cube立方体arc弧curvedline曲线majorarc优弧cylinder柱体minorarc劣弧diameter直径architect建筑师dimension维数，大小breadth宽度endpoint端点chord弦equidistant等距离的circumference周长linesegment直线段cone圆锥radius半径critical临界的pyramid棱锥2.2几何与三角GeometryandTrigonologyNewWords&Expressions:ray射线 sphere球，球面semicircle半圆 surface面，曲面solid立体的，立体thickness厚度

Manyleadinginstitutionsofhigherlearninghaverecognizedthatpositivebenefitscanbegainedbyallwhostudythisbranchofmathematics.

2－AWhystudygeometry?许多居于领导地位的学术机构承认，所有学习这个数学分支的人都将得到确实的受益。Thisisevidentfromthefactthattheyrequirestudyofgeometryasaprerequisitetomatriculationinthoseschools.许多学校把几何的学习作为入学考试的先决条件，从这一点上可以证明。Geometryisasciencethatdealswithformsmadebylines.Astudyofgeometryisanessentialpartofthetrainingofthesuccessfulengineer,scientist,architect,anddraftsman.几何是研究由线所组成的图形的科学。几何的学习是成功工程师，科学家，建筑师和制图员培训的重要部分。Thecarpenter,machinist,stonecutter,artist,anddesignerallapplythefactsofgeometryintheirtrades.Inthiscoursethestudentwilllearnagreatdealaboutgeometricfiguressuchaslines,angles,triangles,circles,anddesignsandpatternsofmanykinds.木匠，机械师，采石者，艺术家和设计师在他们的职业中都应用几何的知识。在这门课程中，学生会学到大量几何图形，例如直线，角，三角形，圆以及许多种设计和模式。Oneofthemostimportantobjectivesderivedfromastudyofgeometryismakingthestudentbemorecriticalinhislistening,readingandthinking.Instudyinggeometryheisledawayfromthepracticeofblindacceptanceofstatementsandideasandistaughttothinkclearlyandcriticallybeforeformingconclusions.学生通过几何的学习而达到的最主要目标是：在听，读，和思考时变得更加审慎。在学习几何的过程中，他们不再盲目地接受一些陈述和思想，而是在得出结论之前学会了清楚和审慎的思考。1.Solidsandplanes.Asolidisathree-dimensionalfigure.Commonexamplesofsolidsarecube,sphere,cylinder,coneandpyramid.2－BSomegeometricalterms立体是一个三维图形，立体常见的例子是立方体，球体，柱体，圆锥和棱锥。Acubehassixfaceswhicharesmoothandflat.Thesefacesarecalledplanesurfacesorsimplyplanes.

Aplanesurfacehastwodimensions,lengthandwidth.Thesurfaceofablackboardorofatabletopisanexampleofaplanesurface.立方体有6个面，都是光滑的和平的，这些面被称为平面曲面或者简称为平面。平面曲面是二维的，有长度和宽度，黑板和桌子上面的面都是平面曲面的例子。2.Linesandlinesegments.Weareallfamiliarwithlines,butitisdifficulttodefinetheterm.Alinemayberepresentedbythemarkmadebymovingapencilorpenacrossapieceofpaper.我们都熟悉直线，但是很难定义直线。可能可以用移动一支铅笔或者钢笔横穿一张纸留下的痕迹来描述直线。Alinemaybeconsideredashavingonlyonedimension,length.Althoughwhenwedrawalinewegiveitbreadthandthickness,wethinkonlyofthelengthofthetracewhenconsideringtheline.直线可以被看做是一维的，即只有长度。尽管我们画一条直线的时候会赋予它宽度和厚度，但是当考虑直线的时候，只考虑痕迹的长度。Apointhasnolength,nowidth,andnothickness,butmarksaposition.Wearefamiliarwithsuchexpressionsaspencilpointandneedlepoint.Werepresentapointbyasmall