小学、初中、高中各种试卷真题知识归纳文案合同PPT等免费下载www.doc985.com拔高点突破02柯西不等式、反柯西不等式与权方和不等式目录01方与法技巧总结...............................................................................................................................202与题型归纳总结...............................................................................................................................2柯西不等式式型一:之直接套公型题......................................................................................................................2柯西不等式式题型二:之根下有正负型..................................................................................................................4柯西不等式高题型三:之次定求低次型..................................................................................................................5柯西不等式高题型四:之低次定求次型..................................................................................................................7柯西不等式式与式题型五:之整分型......................................................................................................................8柯西不等式题型六:之多变量型..............................................................................................................................9柯西不等式题型七:之三角函数型........................................................................................................................11题型八:Aczel不等式..............................................................................................................................................12权方和不等式式与式题型九:之整分综合型........................................................................................................13权方和不等式题型十:之三角函数型....................................................................................................................14权方和不等式题型十一:之杂合型........................................................................................................................1503关过测试.........................................................................................................................................16小学、初中、高中各种试卷真题知识归纳文案合同PPT等免费下载www.doc985.com1、柯西不等式(Cauchy不等式)(1)二元柯西不等式:对于任意的,都有.(2)元柯西不等式:,取等条件:或().2、Aczel不等式(反柯西不等式)设;均为实数,或,则有.当且仅当,成比例时取等.3、权方和不等式(1)二维形式的权方和不等式对于任意的,都有.当且仅当时,等号成立.(2)一般形式的权方和不等式若,,,则,当时等号成立.题型一:柯西不等式式之直接套公型【例1】已知且则的最小值是()A.1B.C.D.2【答案】B【解析】由柯西不等式可得:小学、初中、高中各种试卷真题知识归纳文案合同PPT等免费下载www.doc985.com,即所以,当且仅当即时取等号,故的最小值为,故选:B.式【变1-1】若,则的最小值为()A.25B.8C.D.【答案】C【解析】由柯西不等式,得,∴,∴,当且时,即,且与异号时,,则的最小值为.选:C.式【变1-2】已知a,b,,满足,则的最大值为()A.2B.3C.4D.6【答案】B【解析】设,,,可得,所以.因为,所以,当且仅当,取得最大值6,此时,所以的最大值为.小学、初中、高中各种试卷真题知识归纳文案合同PPT等免费下载www.doc985.com故选:B.柯西不等式式型二:之根下有正型【例2】(2024·高三·山东青岛·期中)柯西不等式(Caulhy-SchwarzLnequality)是法...