Florence Henderson, who began her career as an ingénue soprano in stage musicals in the 1950s but made a more lasting impression on television as the perky 1970s sitcom mom on “The Brady Bunch,” died on Thursday in Los Angeles. She was 82.

Her death was confirmed by David Brokaw, her publicist. He said that she died at Cedars-Sinai Medical Center and that her family said the cause was heart failure.

“She was quite active until she started not feeling well several days ago,” Mr. Brokaw said. “It was felt that she would just bounce back from it.”

Ms. Henderson was making a film in Norway in 1969 when she was asked to appear in the pilot episode of “The Brady Bunch,” an unapologetically upbeat comedy about a woman with three daughters who meets, marries and makes a sunny suburban California home with a widower who has three sons.