2013全国中考数学试题分类汇编----无理数和实数

《2013全国中考数学试题分类汇编----无理数和实数》由会员上传分享，免费在线阅读，更多相关内容在教育资源-天天文库。

1、（2013•郴州）计算：

2、﹣

3、+（2013﹣）0﹣（）﹣1﹣2sin60°．考点：实数的运算；零指数幂；负整数指数幂；特殊角的三角函数值．3718684专题：计算题．分析：先分别根据0指数幂及负整数指数幂的计算法则，特殊角的三角函数值计算出各数，再根据实数混合运算的法则进行计算即可．解答：解：原式=2+1﹣3﹣2×=2+1﹣3﹣=﹣2．点评：本题考查的是实数的运算，熟知0指数幂及负整数指数幂的计算法则，特殊角的三角函数值是解答此题的关键．　（2013，娄底）计算：_______________（2013•湘西州）计算：（）﹣1﹣﹣sin30°．考点：实数的运算；

4、负整数指数幂；特殊角的三角函数值专题：计算题．分析：本题涉及负指数幂、平方根、特殊角的三角函数值等考点．针对每个考点分别进行计算，然后根据实数的运算法则求得计算结果．解答：解：原式=﹣2﹣=3﹣2﹣=．点评：本题考查实数的综合运算能力，是各地中考题中常见的计算题型．解决此类题目的关键是熟记特殊角的三角函数值，熟练掌握负指数幂、平方根、特殊角的三角函数值等考点的运算．（2013，永州）计算：2013•株洲）计算：．考点：实数的运算；特殊角的三角函数值．3718684专题：计算题．分析：instrumenthasasingletestcondition,willbe

5、transferredtothecoordinationofthetestphase,theinstrumentaccordingtothestand-alonetrialsscheduled,withtheprocesspreparationoftestsolutions,equippedwithprofessionaltechniciansandskilledworkers,toensuresafetyandquality.6.weldingengineeringconstructionprogramme6.1thisengineeringusedconst

6、ructionspecification6.1.1siteequipment,andindustrialpipelineweldingengineeringconstructionandtheacceptancespecificationGB50268-976.1.2oilchemicaltoxic,andcanburningmediapipelineengineeringconstructionandtheacceptancespecificationSH3501-20026.1.3oilchemicallowtemperaturesteelweldingpr

7、oceduresSH/T3520-20046.1.4oilchemicalchromenickelAustrian'sbodysteel,andironnickelalloyandnickelalloypipelineweldingproceduresSH/T3523-19996.1.5SHJ520-92petrochemicalengineeringtechnicalspecificationforweldingofCR-MOheat-resistantsteelpipe6.1.6ofthepressurevesselNDT4730-946.2JBweldpr

8、eparation6.2.1constructionaccordingtothematerialsoftheprojectspecificationsandweldingmethods,providingqualifiedweldingprocedurequalificationreport.6.2.2qualifiedweldingprocedurequalificationbasedonthepreparationofweldinginstruction,guidethewelderweldingoperations.6.2.3whereparticipat

9、ioninsitewelding,mustbeinpossessionofboilerandpressurevesselweldercertificatesissuedbytheLaborDepartment.6.2.4whereinvolvedinthepipeandsteelstructureweldingwelders,welderbeforeentryexaminationsshouldattendtheowners,andconstructionshouldbemadewithinthescopeandeligibilityapprovedbytheq

10、ualityandtec