{"id":2875,"date":"2025-06-07T15:57:46","date_gmt":"2025-06-07T15:57:46","guid":{"rendered":"https:\/\/diznr.com\/?p=2875"},"modified":"2025-06-07T15:57:46","modified_gmt":"2025-06-07T15:57:46","slug":"gate-1989-subject-theory-of-computation-topic-automata-finite","status":"publish","type":"post","link":"https:\/\/www.reilsolar.com\/pdf\/gate-1989-subject-theory-of-computation-topic-automata-finite\/","title":{"rendered":"GATE 1989 Subject &#8211; Theory Of Computation Topic -Finite Automata"},"content":{"rendered":"<p>GATE 1989 Subject &#8211; Theory Of Computation Topic -Finite Automata<\/p>\n<p>[fvplayer id=&#8221;154&#8243;]<\/p>\n<p class=\"\" data-start=\"0\" data-end=\"146\">Here&#8217;s a focused breakdown of the <strong data-start=\"34\" data-end=\"47\">GATE 1989<\/strong> paper, particularly for the <strong data-start=\"76\" data-end=\"101\">Theory of Computation<\/strong> subject under the topic <strong data-start=\"126\" data-end=\"145\">Finite Automata<\/strong>:<\/p>\n<hr class=\"\" data-start=\"148\" data-end=\"151\" \/>\n<h2 class=\"\" data-start=\"153\" data-end=\"198\">\ud83d\udcdd <strong data-start=\"159\" data-end=\"196\">GATE 1989 \u2013 Theory of Computation<\/strong><\/h2>\n<h3 class=\"\" data-start=\"199\" data-end=\"232\">\ud83d\udcda <strong data-start=\"206\" data-end=\"232\">Topic: Finite Automata<\/strong><\/h3>\n<h3 class=\"\" data-start=\"234\" data-end=\"267\">\ud83d\udd39 <strong data-start=\"241\" data-end=\"267\">Key Concepts to Revise<\/strong><\/h3>\n<p class=\"\" data-start=\"268\" data-end=\"423\">Before jumping into specific questions or examples from the 1989 paper, it\u2019s important to revise the following key concepts related to <strong data-start=\"403\" data-end=\"422\">Finite Automata<\/strong>:<\/p>\n<ol data-start=\"425\" data-end=\"804\">\n<li class=\"\" data-start=\"425\" data-end=\"467\">\n<p class=\"\" data-start=\"428\" data-end=\"467\"><strong data-start=\"428\" data-end=\"467\">Deterministic Finite Automata (DFA)<\/strong><\/p>\n<\/li>\n<li class=\"\" data-start=\"468\" data-end=\"514\">\n<p class=\"\" data-start=\"471\" data-end=\"514\"><strong data-start=\"471\" data-end=\"514\">Non-Deterministic Finite Automata (NFA)<\/strong><\/p>\n<\/li>\n<li class=\"\" data-start=\"515\" data-end=\"548\">\n<p class=\"\" data-start=\"518\" data-end=\"548\"><strong data-start=\"518\" data-end=\"548\">Equivalence of DFA and NFA<\/strong><\/p>\n<\/li>\n<li class=\"\" data-start=\"549\" data-end=\"578\">\n<p class=\"\" data-start=\"552\" data-end=\"578\"><strong data-start=\"552\" data-end=\"578\">Conversion: NFA to DFA<\/strong><\/p>\n<\/li>\n<li class=\"\" data-start=\"579\" data-end=\"605\">\n<p class=\"\" data-start=\"582\" data-end=\"605\"><strong data-start=\"582\" data-end=\"605\">Minimization of DFA<\/strong><\/p>\n<\/li>\n<li class=\"\" data-start=\"606\" data-end=\"654\">\n<p class=\"\" data-start=\"609\" data-end=\"654\"><strong data-start=\"609\" data-end=\"654\">Regular Languages and Regular Expressions<\/strong><\/p>\n<\/li>\n<li class=\"\" data-start=\"655\" data-end=\"685\">\n<p class=\"\" data-start=\"658\" data-end=\"685\"><strong data-start=\"658\" data-end=\"685\">Language accepted by FA<\/strong><\/p>\n<\/li>\n<li class=\"\" data-start=\"686\" data-end=\"732\">\n<p class=\"\" data-start=\"689\" data-end=\"732\"><strong data-start=\"689\" data-end=\"732\">Closure Properties of Regular Languages<\/strong><\/p>\n<\/li>\n<li class=\"\" data-start=\"733\" data-end=\"804\">\n<p class=\"\" data-start=\"736\" data-end=\"804\"><strong data-start=\"736\" data-end=\"804\">Limitations of FA (e.g., not recognizing context-free languages)<\/strong><\/p>\n<\/li>\n<\/ol>\n<hr class=\"\" data-start=\"806\" data-end=\"809\" \/>\n<h3 class=\"\" data-start=\"811\" data-end=\"871\">\ud83d\udccc <strong data-start=\"818\" data-end=\"871\">Sample GATE 1989 Style Question (Finite Automata)<\/strong><\/h3>\n<p class=\"\" data-start=\"873\" data-end=\"929\"><strong data-start=\"873\" data-end=\"880\">Q1.<\/strong><br data-start=\"880\" data-end=\"883\" \/>Which of the following statements is <strong data-start=\"920\" data-end=\"928\">true<\/strong>?<\/p>\n<p class=\"\" data-start=\"931\" data-end=\"1085\">a) Every NFA is also a DFA<br data-start=\"957\" data-end=\"960\" \/>b) Every DFA is also an NFA<br data-start=\"987\" data-end=\"990\" \/>c) Every regular language is not accepted by DFA<br data-start=\"1038\" data-end=\"1041\" \/>d) NFA can recognize non-regular languages<\/p>\n<p class=\"\" data-start=\"1087\" data-end=\"1114\"><strong data-start=\"1087\" data-end=\"1112\">\u2705 Correct Answer: (b)<\/strong><\/p>\n<blockquote data-start=\"1115\" data-end=\"1451\">\n<p class=\"\" data-start=\"1117\" data-end=\"1451\">Every DFA is also an NFA (a special case of NFA with exactly one transition per symbol per state).<br data-start=\"1215\" data-end=\"1218\" \/>Option (a) is false because not all NFAs are DFAs without conversion.<br data-start=\"1289\" data-end=\"1292\" \/>Option (c) is false because <strong data-start=\"1322\" data-end=\"1369\">every regular language is accepted by a DFA<\/strong>.<br data-start=\"1370\" data-end=\"1373\" \/>Option (d) is false because <strong data-start=\"1403\" data-end=\"1450\">NFAs cannot recognize non-regular languages<\/strong>.<\/p>\n<\/blockquote>\n<hr class=\"\" data-start=\"1453\" data-end=\"1456\" \/>\n<h3 class=\"\" data-start=\"1458\" data-end=\"1496\">\ud83e\udde0 <strong data-start=\"1465\" data-end=\"1496\">Conceptual Question Example<\/strong><\/h3>\n<p class=\"\" data-start=\"1498\" data-end=\"1589\"><strong data-start=\"1498\" data-end=\"1505\">Q2.<\/strong><br data-start=\"1505\" data-end=\"1508\" \/>Let L be a language accepted by a DFA. Which of the following statements is true?<\/p>\n<p class=\"\" data-start=\"1591\" data-end=\"1726\">a) L is necessarily infinite<br data-start=\"1619\" data-end=\"1622\" \/>b) Complement of L is not regular<br data-start=\"1655\" data-end=\"1658\" \/>c) L is regular<br data-start=\"1673\" data-end=\"1676\" \/>d) L cannot be described by a regular expression<\/p>\n<p class=\"\" data-start=\"1728\" data-end=\"1755\"><strong data-start=\"1728\" data-end=\"1753\">\u2705 Correct Answer: (c)<\/strong><\/p>\n<blockquote data-start=\"1756\" data-end=\"1829\">\n<p class=\"\" data-start=\"1758\" data-end=\"1829\">Any language accepted by a DFA is <strong data-start=\"1792\" data-end=\"1828\">by definition a regular language<\/strong>.<\/p>\n<\/blockquote>\n<hr class=\"\" data-start=\"1831\" data-end=\"1834\" \/>\n<h3 class=\"\" data-start=\"1836\" data-end=\"1896\">\ud83d\udccc <strong data-start=\"1843\" data-end=\"1896\">Useful Tips for Finite Automata Questions in GATE<\/strong><\/h3>\n<ul data-start=\"1898\" data-end=\"2201\">\n<li class=\"\" data-start=\"1898\" data-end=\"1964\">\n<p class=\"\" data-start=\"1900\" data-end=\"1964\">Always draw a <strong data-start=\"1914\" data-end=\"1931\">state diagram<\/strong> to better visualize transitions.<\/p>\n<\/li>\n<li class=\"\" data-start=\"1965\" data-end=\"2036\">\n<p class=\"\" data-start=\"1967\" data-end=\"2036\">Practice converting <strong data-start=\"1987\" data-end=\"2010\">regular expressions<\/strong> to <strong data-start=\"2014\" data-end=\"2020\">FA<\/strong> and vice versa.<\/p>\n<\/li>\n<li class=\"\" data-start=\"2037\" data-end=\"2115\">\n<p class=\"\" data-start=\"2039\" data-end=\"2115\">Be familiar with <strong data-start=\"2056\" data-end=\"2076\">DFA minimization<\/strong> techniques (state equivalence method).<\/p>\n<\/li>\n<li class=\"\" data-start=\"2116\" data-end=\"2201\">\n<p class=\"\" data-start=\"2118\" data-end=\"2201\">Remember that <strong data-start=\"2132\" data-end=\"2161\">every DFA is a unique NFA<\/strong>, but the reverse requires construction.<\/p>\n<\/li>\n<\/ul>\n<hr class=\"\" data-start=\"2203\" data-end=\"2206\" \/>\n<h3 class=\"\" data-start=\"2208\" data-end=\"2248\">\ud83d\udcd8 <strong data-start=\"2215\" data-end=\"2248\">Recommended Practice Problems<\/strong><\/h3>\n<ol data-start=\"2249\" data-end=\"2470\">\n<li class=\"\" data-start=\"2249\" data-end=\"2321\">\n<p class=\"\" data-start=\"2252\" data-end=\"2321\">Construct a DFA that accepts strings over <code data-start=\"2294\" data-end=\"2301\">{0,1}<\/code> that end with <code data-start=\"2316\" data-end=\"2320\">01<\/code>.<\/p>\n<\/li>\n<li class=\"\" data-start=\"2322\" data-end=\"2354\">\n<p class=\"\" data-start=\"2325\" data-end=\"2354\">Convert the given NFA to DFA.<\/p>\n<\/li>\n<li class=\"\" data-start=\"2355\" data-end=\"2401\">\n<p class=\"\" data-start=\"2358\" data-end=\"2401\">Minimize a given DFA and find its language.<\/p>\n<\/li>\n<li class=\"\" data-start=\"2402\" data-end=\"2470\">\n<p class=\"\" data-start=\"2405\" data-end=\"2470\">Given a regular expression, construct the equivalent NFA and DFA.<\/p>\n<\/li>\n<\/ol>\n<hr class=\"\" data-start=\"2472\" data-end=\"2475\" \/>\n<p class=\"\" data-start=\"2477\" data-end=\"2635\">Would you like the <strong data-start=\"2496\" data-end=\"2530\">exact GATE 1989 question paper<\/strong> with solutions, or should I generate a <strong data-start=\"2570\" data-end=\"2594\">custom practice test<\/strong> based on that year&#8217;s style and syllabus?<\/p>\n<p class=\"\" data-start=\"0\" data-end=\"173\">Certainly! Let&#8217;s delve into a specific question from the <strong data-start=\"57\" data-end=\"70\">GATE 1989<\/strong> examination under the subject <strong data-start=\"101\" data-end=\"126\">Theory of Computation<\/strong>, focusing on the topic of <strong data-start=\"153\" data-end=\"172\">Finite Automata<\/strong>.<\/p>\n<hr class=\"\" data-start=\"175\" data-end=\"178\" \/>\n<h3 class=\"\" data-start=\"180\" data-end=\"224\">\ud83d\udcd8 <strong data-start=\"187\" data-end=\"224\">GATE 1989 \u2013 Theory of Computation<\/strong><\/h3>\n<h4 class=\"\" data-start=\"225\" data-end=\"259\">\ud83e\udde0 <strong data-start=\"233\" data-end=\"259\">Topic: Finite Automata<\/strong><\/h4>\n<p class=\"\" data-start=\"261\" data-end=\"274\"><strong data-start=\"261\" data-end=\"274\">Question:<\/strong><\/p>\n<p class=\"\" data-start=\"276\" data-end=\"344\"><em data-start=\"276\" data-end=\"344\">Is the class of regular sets closed under infinite union? Explain.<\/em><\/p>\n<p class=\"\" data-start=\"346\" data-end=\"357\"><strong data-start=\"346\" data-end=\"357\">Answer:<\/strong><\/p>\n<p class=\"\" data-start=\"359\" data-end=\"433\"><span class=\"relative -mx-px my-[-0.2rem] rounded px-px py-[0.2rem] transition-colors duration-100 ease-in-out\">The class of regular languages is <strong data-start=\"34\" data-end=\"48\">not closed<\/strong> under infinite union.<\/span><\/p>\n<p class=\"\" data-start=\"435\" data-end=\"451\"><strong data-start=\"435\" data-end=\"451\">Explanation:<\/strong><\/p>\n<p class=\"\" data-start=\"453\" data-end=\"527\"><span class=\"relative -mx-px my-[-0.2rem] rounded px-px py-[0.2rem] transition-colors duration-100 ease-in-out\">Regular languages are closed under operations such as union, intersection, and complement when applied <strong data-start=\"103\" data-end=\"115\">finitely<\/strong>. However, when considering an <strong data-start=\"146\" data-end=\"158\">infinite<\/strong> union of regular languages, the resulting language may not be regular.<\/span><\/p>\n<p class=\"\" data-start=\"529\" data-end=\"541\"><strong data-start=\"529\" data-end=\"541\">Example:<\/strong><\/p>\n<p class=\"\" data-start=\"543\" data-end=\"573\">Consider the set of languages:<\/p>\n<ul data-start=\"575\" data-end=\"785\">\n<li class=\"\" data-start=\"575\" data-end=\"614\">\n<p class=\"\" data-start=\"577\" data-end=\"614\"><span class=\"relative -mx-px my-[-0.2rem] rounded px-px py-[0.2rem] transition-colors duration-100 ease-in-out\">L\u2081 = { a }<\/span><\/p>\n<\/li>\n<li class=\"\" data-start=\"615\" data-end=\"656\">\n<p class=\"\" data-start=\"617\" data-end=\"656\"><span class=\"relative -mx-px my-[-0.2rem] rounded px-px py-[0.2rem] transition-colors duration-100 ease-in-out\">L\u2082 = { aa }<\/span><\/p>\n<\/li>\n<li class=\"\" data-start=\"657\" data-end=\"698\">\n<p class=\"\" data-start=\"659\" data-end=\"698\"><span class=\"relative -mx-px my-[-0.2rem] rounded px-px py-[0.2rem] transition-colors duration-100 ease-in-out\">L\u2083 = { aaa }<\/span><\/p>\n<\/li>\n<li class=\"\" data-start=\"699\" data-end=\"704\">\n<p class=\"\" data-start=\"701\" data-end=\"704\">&#8230;<\/p>\n<\/li>\n<li class=\"\" data-start=\"705\" data-end=\"785\">\n<p class=\"\" data-start=\"707\" data-end=\"785\"><span class=\"relative -mx-px my-[-0.2rem] rounded px-px py-[0.2rem] transition-colors duration-100 ease-in-out\">L\u2099 = { a\u207f }<\/span><\/p>\n<\/li>\n<\/ul>\n<p class=\"\" data-start=\"787\" data-end=\"840\">Each L\u2099 is regular. Now, consider the infinite union:<\/p>\n<p class=\"\" data-start=\"842\" data-end=\"920\"><span class=\"relative -mx-px my-[-0.2rem] rounded px-px py-[0.2rem] transition-colors duration-100 ease-in-out\">L = \u22c3\u2099\u208c\u2081^\u221e L\u2099 = { a, aa, aaa, aaaa, &#8230; } = { a\u207f | n \u2265 1 }<\/span><\/p>\n<p class=\"\" data-start=\"922\" data-end=\"1000\"><span class=\"relative -mx-px my-[-0.2rem] rounded px-px py-[0.2rem] transition-colors duration-100 ease-in-out\">This language is regular and can be represented by the regular expression <strong data-start=\"74\" data-end=\"80\">a\u207a<\/strong>.<\/span><\/p>\n<p class=\"\" data-start=\"1002\" data-end=\"1040\">However, consider a different example:<\/p>\n<p class=\"\" data-start=\"1042\" data-end=\"1136\">Let L\u2099 = { a\u207fb\u207f } for each n \u2265 1. Each L\u2099 is finite and thus regular. Now, consider the union:<\/p>\n<p class=\"\" data-start=\"1138\" data-end=\"1216\"><span class=\"relative -mx-px my-[-0.2rem] rounded px-px py-[0.2rem] transition-colors duration-100 ease-in-out\">L = \u22c3\u2099\u208c\u2081^\u221e L\u2099 = { ab, aabb, aaabbb, &#8230; } = { a\u207fb\u207f | n \u2265 1 }<\/span><\/p>\n<p class=\"\" data-start=\"1218\" data-end=\"1296\"><span class=\"relative -mx-px my-[-0.2rem] rounded px-px py-[0.2rem] transition-colors duration-100 ease-in-out\">This language is <strong data-start=\"17\" data-end=\"24\">not<\/strong> regular, as it requires matching numbers of a&#8217;s and b&#8217;s, which cannot be done with a finite automaton.<\/span><\/p>\n<p class=\"\" data-start=\"1298\" data-end=\"1387\">Therefore, <span class=\"relative -mx-px my-[-0.2rem] rounded px-px py-[0.2rem] transition-colors duration-100 ease-in-out\">the infinite union of regular languages is <strong data-start=\"43\" data-end=\"62\">not necessarily<\/strong> regular, indicating that the class of regular languages is <strong data-start=\"122\" data-end=\"136\">not closed<\/strong> under infinite union.<\/span><\/p>\n<hr class=\"\" data-start=\"1389\" data-end=\"1392\" \/>\n<p class=\"\" data-start=\"1394\" data-end=\"1572\">If you&#8217;re interested in exploring more questions from GATE 1989 or other years, or if you need further clarification on topics within the Theory of Computation, feel free to ask!<\/p>\n<h3 data-start=\"1394\" data-end=\"1572\"><a href=\"https:\/\/www.vssut.ac.in\/lecture_notes\/lecture1423813120.pdf\" target=\"_blank\" rel=\"noopener\">GATE 1989 Subject &#8211; Theory Of Computation Topic -Finite Automata<\/a><\/h3>\n","protected":false},"excerpt":{"rendered":"<p>GATE 1989 Subject &#8211; Theory Of Computation Topic -Finite Automata [fvplayer id=&#8221;154&#8243;] Here&#8217;s a focused breakdown of the GATE 1989 paper, particularly for the Theory of Computation subject under the topic Finite Automata: \ud83d\udcdd GATE 1989 \u2013 Theory of Computation \ud83d\udcda Topic: Finite Automata \ud83d\udd39 Key Concepts to Revise Before jumping into specific questions or [&hellip;]<\/p>\n","protected":false},"author":71,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-2875","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/www.reilsolar.com\/pdf\/wp-json\/wp\/v2\/posts\/2875","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.reilsolar.com\/pdf\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.reilsolar.com\/pdf\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.reilsolar.com\/pdf\/wp-json\/wp\/v2\/users\/71"}],"replies":[{"embeddable":true,"href":"https:\/\/www.reilsolar.com\/pdf\/wp-json\/wp\/v2\/comments?post=2875"}],"version-history":[{"count":0,"href":"https:\/\/www.reilsolar.com\/pdf\/wp-json\/wp\/v2\/posts\/2875\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.reilsolar.com\/pdf\/wp-json\/wp\/v2\/media?parent=2875"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.reilsolar.com\/pdf\/wp-json\/wp\/v2\/categories?post=2875"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.reilsolar.com\/pdf\/wp-json\/wp\/v2\/tags?post=2875"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}