Trouver-la-somme-de-S-n-Si-S-n-1-11-111-1111-111- Tinku Tara June 4, 2023 Algebra 0 Comments FacebookTweetPin Question Number 175407 by Stephan last updated on 29/Aug/22 TrouverlasommedeSn―SiSn=1+11+111+…+1111…111 Answered by Rasheed.Sindhi last updated on 29/Aug/22 Sn=1+11+111+…+1111…119Sn=9+99+999+…+999…99=(10−1)+(100−1)+(1000−1)+…nterms=(10+100+1000+…nterms)−n=10(10n−1)10−1−n=10(10n−1)−9n9Sn=10n+1−9n−1081 Answered by Ar Brandon last updated on 29/Aug/22 un=1+11+111+1111+…⇒un=10n−19⇒Σun=109(10n−19)−n9 Terms of Service Privacy Policy Contact: info@tinkutara.com FacebookTweetPin Post navigation Previous Previous post: Can-positive-integers-a-b-c-be-found-such-that-a-3-b-3-c-3-Next Next post: Question-44336 Leave a Reply Cancel replyYour email address will not be published. Required fields are marked *Comment * Name * Save my name, email, and website in this browser for the next time I comment.