洛阳市2023-2024学年高二质量检测(2024.6)数学.考卷答案

洛阳市2023-2024学年高二质量检测(2024.6)数学.考卷答案试卷答案,我们目前收集并整理关于洛阳市2023-2024学年高二质量检测(2024.6)数学.考卷答案得系列试题及其答案,更多试题答案请关注本网站↓↓↓

试题答案

洛阳市2023-2024学年高二质量检测(2024.6)数学.考卷答案试卷答案

以下是该试卷的部分内容或者是答案亦或者啥也没有,更多试题答案请捕获只因

task,soinsteadofspendingtoomuchtimethinkingaboutit,theyrelyonconsumptionstandardstohelpwhenchoosinghowmuchtoeat.Consumptionmaybeinfluencedbyhowmuchonetypicallybuysorconsumes.Externalfactorshavebeenshowntoinfluenceone'sestimateofhowmuchtheyhaveeaten.Evenwhenpeopleweregivenin-formationthatlargerpackagesizesoftencauseindividualstoun-derestimateconsumptionby20%,manyofthesepeopleinfieldandlabstudiesincorrectlysaidtheywerenotaffectedbypackagesize.Howmuchoneeatsinadistracting(分心的)environmentdependsonwhetherthepersonistryingtomonitortheirintake.Eatingisacomplexprocessthatissometimesdifficulttomoni-

分析把已知数列递推式变形,可得数列{$\frac{1}{{a}_{n}}$}构成以$\frac{1}{2}$为首项,以2为公差的等差数列,求出等差数列的通项公式后可得数列{an}的通项公式.

解答解:由$\frac{1}{{a}_{n}}$=$\frac{1}{{a}_{n-1}}$+2(n≥2),得$\frac{1}{{a}_{n}}-\frac{1}{{a}_{n-1}}=2(n≥2)$,
又a1=2,∴$\frac{1}{{a}_{1}}=\frac{1}{2}$,
则数列{$\frac{1}{{a}_{n}}$}构成以$\frac{1}{2}$为首项,以2为公差的等差数列,
则$\frac{1}{{a}_{n}}=\frac{1}{2}+2(n-1)=\frac{4n-3}{2}$,
∴${a}_{n}=\frac{2}{4n-3}$.
故答案为:$\frac{2}{4n-3}$.

点评本题考查数列递推式,考查了等差关系的确定,训练了等差数列通项公式的求法,是中档题.