What was going on when I was born?

''It is becoming clearer in the international community that terrorism is a menace to everyone.'' - Secretary of State George P. Shultz. [A10:3.]

The Economy The economy expanded at a 3.3 percent annual rate in the third quarter, somewhat faster than first estimated, the Commerce Department said. But most analysts saw the performance as mediocre. The growth reflected booming automobile sales and production, which are expected to slow in coming months, and big Government spending for farm price supports and military purchases. [Page A1.] Housing construction fell 9.3 percent in September, the steepest drop since May. Many analysts said the downturn was a one-month aberration. [D1.] Manufacturers cut back operations to 80.2 percent of capacity in September, the Fed said. [D22.] President Reagan said he was running out of time to win public support for changes in the tax system. [D1.]

The nation's economy expanded at a 3.3 percent annual rate during the third quarter, somewhat faster than earlier estimated, the Commerce Department said today. Although the economic growth rate for the quarter was triple that of the first six months of the year, most analysts viewed the rebound as only a mediocre performance of uncertain durability. ''It's just a moderate pickup,'' said Walter M. Cadette, a vice president at the Morgan Guaranty Trust Company. ''The economy does not have a great deal of punch behind it.''

The crisis affecting the United States semiconductor industry claimed its first major victim yesterday, when the United Technologies Corporation announced the closing of its Mostek Corporation subsidiary. The move would take effect immediately, United Technologies said. However, late yesterday, executives of Mostek issued a memorandum to employees saying they were ''actively pursuing options to maintain an ongoing downsized business'' independent of United Technologies. One of the options being studied, according to a United Technologies spokesman, is a leveraged buyout of part of Mostek's business.

International Italy's Prime Minister resigned after making a dramatic speech to Parliament in which he spoke of his ''bitterness'' over American actions after the hijacking of the liner Achille Lauro. In his address, Bettino Craxi also asserted that an unauthorized United States aircraft had followed a plane taking a senior Palestinian official and an associate from Sicily to Rome. [Page A1, Column 6.] The U.S. hopes to keep friendly ties with Italy but has no regret for its actions that precipitated the resignation of Prime Minister Craxi, according to a spokesman for the Reagan Administration. [A1:5.]

''THE FIRST PAINTERS OF THE KING,'' at Stair Sainty Matthiesen, 141 East 69th Street, is subtitled ''French Royal Taste From Louis XIV to the Revolution.'' Neither phrase, in itself, is likely to draw a crowd, yet the exhibition is one that does us all a service. It is full, moreover, of works of art that are both learned and voluptuous, majestic and highly energized. Poussin apart, French 17th-century painters have never had a large popular following in this country. If you drop the name of Charles Le Brun at the dinner table, your neighbors will not fall silent in awed attention. Yet for most of the second half of the 17th century in France - one of the high points, after all, of European civilization - Le Brun was Mr. Painting, with a long string of major commissions to reinforce his stature.

A judge yesterday imposed an unusual ''interim sentence'' on seven black revolutionaries, ordering them to do community service for three months before he decides whether to put them in prison. The judge, Robert L. Carter of Federal District Court in Manhattan, said he had a ''problem'' choosing between the Government's view that the defendants were a ''menace'' and their own view that they were struggling to ''liberate the black masses.'' ''You can't take the law into your hands,'' Judge Carter admonished the defendants, telling them that their struggle must be lawful and ''can't be with guns.'' #10 Hours a Week The judge said a probation officer would pick separate community programs for the defendants, who must each work 10 hours a week and avoid ''weapons of any kind.''

The Prime Minister of Italy resigned today after a speech to Parliament in which he spoke of his ''bitterness'' over actions by the United States in the aftermath of the hijacking of the liner Achille Lauro. The collapse of the 26-month-old coalition Cabinet led by Prime Minister Bettino Craxi produced one of the most dramatic days in Italian politics in several years. The Prime Minister was forced to resign after Giovanni Spadolini, the Defense Minister, pulled his Republican Party out of the Government on Wednesday to protest its handling of the hijacking and its decision to free Mohammed Abbas, a Palestinian guerrilla sought by the United States. The United States also condemned Mr. Craxi's decision to release Mr. Abbas. Final Cabinet Meeting After a final Cabinet meeting today, which the Republicans did not attend, Mr. Craxi made his address and then drove to the Presidential Palace to hand his resignation to President Francesco Cossiga.

The glittery commercial centerpiece of Battery Park City officially opened for business yesterday in ceremonies that were imbued with a sense that something more was involved than a cluster of office towers. Called the World Financial Center, those towers are imposing in their own right - they will cost $1.5 billion, contain seven million square feet of office space, decorate the western tip of Manhattan with a distinctive new skyline and provide homes for some of the most prestigious companies on Wall Street - Merrill Lynch & Company, Shearson/American Express, Dow Jones & Company, and Oppenheimer & Company. A Symbol of Change But symbolically, they represent even more, because there is perhaps no other piece of New York City that so embodies the volatile changes -economic, political, and philosophic - that have swept through the city over the last 15 years. At once, these four towers, built by a Canadian development company, Olympia & York, and distinctively topped with stylized copper roofs, symbolize the city's growing preeminence as a financial capital, its emergence from a dark decade of fiscal crises and corporate departures, and the muting of the traditional liberal politics over which most of Battery Park City's early battles were fought.

TRIBECA is a swath of old New York, complete with food and textile wholesalers, gritty warehouses, ungentrified neighborhood bars, and century-old cast-iron buildings. At the same time, it is a swath of the very new New York, with all kinds of avant-garde art galleries and performance spaces from Franklin Furnace to the Puppet Loft. The new TriBeCa first attracted New Yorkers when the action spilled over from neighboring SoHo a decade ago. Once known as Washington Market, the area was rechristened TriBeCa (for Triangle Below Canal) in 1974 by an undoubtedly whimsical geographer at the Office of Lower Manhattan Development. Less touristy than SoHo, with fewer boutiques, TriBeCa has maintained its raw quality. At the same time, it has emerged as one of the fastest-growing areas of Manhattan. What's more, some of the city's most fashionable restaurants and nightspots have opened there in recent years. It is a fascinating area, to be explored on foot and enjoyed in different ways, at different times. A daytime visit could include an informal walking tour of its rich architectural heritage, and its galleries and shops. After dark, a multitude of restaurants, performance spaces, jazz bars and nightclubs come to life, and many stay that way till the early hours of the morning.

The Reagan Administration said today that it hoped to maintain ''close and friendly relations'' with Italy but had no regret for actions that led to the resignation of Prime Minister Bettino Craxi. A White House spokesman, Edward P. Djerejian, praised the overall policies of Mr. Craxi's Government, but he repeated that ''we were clearly disappointed'' by Mr. Craxi's decision to allow the departure to Yugoslavia last Saturday of Mohammed Abbas, the Palestinian official named in an American arrest warrant for a role in the hijacking of the Italian cruise ship Achille Lauro. Craxi's Policies Praised American officials said relations with Italy had been strong during Mr. Craxi's tenure, with the United States particularly grateful for his support of NATO policies and his accepting the deployment of cruise missiles in Sicily despite Soviet objections. An American protest on Sunday over the decision to allow Mr. Abbas to leave Italy was seized on by Defense Minister Giovanni Spadolini, whose Republican Party was a member of the coalition government.

President Reagan said today that he was running out of time to create public support for his planned modification of the Federal income tax system. Mr. Reagan's acknowledgement followed warnings from Congressional leaders, including supporters and opponents of the plan, that it will be difficult to pass the sweeping measure by the end of the year. In making the point to leaders of a group of ethnic and fraternal organizations who were invited to the White House today, the President suggested that the plan could still be enacted by the time that Congress adjourns. But for that to happen, he said, local support would have to be generated by the leaders, because he no longer had the time to do so himself.