Sen. Edward W. Brooke (R-Mass.) took several thousand dollars in income tax exemptions between 1970 and 1975 by claiming his two daughters as dependents while they were married and living away from his home, according to documents obtained by The Washington Post.

According to the U.S. Internal Revenue Code a taxpayer may claim a dependent when he pays over half of the support of the dependent during the tax year. Both daughters, in separate interviews, say that their father did not supply anywhere near half their support during that time.

The documents and other information made available to the Post also raise questions about the source of several thousand dollars in out-of-pocket funds spent by Brooke each year.

Brooke is under investigation by the Senate Select Committee on Ethics for possible financial irregularities in connection with misstatements he has admitted he made about his financial affairs.

Last week, the Middlesex, Mass., district attorney said he would open an investigation into questions of possible perjury by Brooke on papers he filed in connection with a pending divorce from his wife, Remigia. The Massachusetts Welfare Department is investigating the possibility of Medicare fraud connected with the estate of Brooke's mother-in-law.

A spokesman for the Massachusetts senator said yesterday that Brooke would not respond to any questions about his financial affairs raised by the press. Instead, he said, Brooke would answer all financial questions before the ethics committee, scheduled to conduct its questioning of Brooke in secret.

According to Brooke's tax returns he listed his eldest daughter, Remi, as a dependent four times between 1970 and 1975, taking the standard exemption in each year. The total exemptions for Remi Brooke on the tax returns come to $2,800.

Remi Brooke, who was married in 1968 and again in 1972, said in interviews last week that she had not received any support from her father after her first marriage. She said she had lived apart from the Brooke family home since 1968 and could not explain why her father listed her as a dependent.

The senator's younger daughter, Edwina, said in an interview from her home in Paris that she was not supported by Brooke after her graduation from college in 1974. Brooke listed Edwina as a dependent on his 1975 tax return and claimed a $750 exemption for her.

"After my graduation I was completely self-supporting," Edwina Brooke said. "My father never gave me a cent."

Both Remi and Edwina Brooke have publicly sided with their mother in the bitter divorce proceedings between Brooke and his wife. The divorce was to have become final last Thursday, but a Massachusetts judge ruled last week that Mrs. Brooke could have a new divorce trial if she wanted one because of misstatements by the senator on his divorce papers.

Sources close to Brooke said yesterday that his tax returns between 1973 and 1975 had been audited by the Internal Revenue Service and that no exemptions were questioned. It could not be learned, however, if the audit included a full check of the accuracy of the exemptions.

An examination of disbursements from an account maintained by Brooke from 1972 through 1977 - which was used by the senator to pay for occasional birthday and wedding gifts as well as for some travel expenses for his family - shows no regular or substantial payments from the account to the Brooke daughters while they lived away from home.

The account is in the name of Teresa Ferrari-Scacco, Brooke's mother-in-law, who turned over the management of the funds to Brooke after she received the money as a settlement from an automobile accident. Brooke has admitted making false statements about the source of the money. It could not be learned yesterday whether another account existed which Brooke may have used to support his daughters.

According to the U.S. Internal Revenue Code a taxpayer may claim a dependent when he pays over half of the support of the dependent during the tax year. Both daughters, in separate interviews, say that their father did not supply anywhere near half their support during that time.

Other documents obtained by The Washington Post indicate that Brooke's office manager swore in a deposition in the divorce case in 1976 that she handled all of Brooke's income and paid all his personal bills. But when asked in the deposition the source of his personal spending money, in a vague, ambiguous answer, she was unable to account for it.

In the deposition, Carol Connelly, still on Brooke's staff, said she kept the senator's checkbook locked in her office. She said she deposited in the bank "every penny" of Brooke's income, including his paycheck, speaking honoraria, foreign expense reimbursements and rental property income.

Connelly said she wrote checks for Brooke's mortgage payments, garage rent, telephone bills and housecleaner. But she could not account for where he got his personal funds for food and other out-of-pocket expenses.

Occasionally, she said, she gave Brooke blank checks. She did not say how much Brooke filled in the checks for or how frequently she gave him the checks. However, other sources who have seen all of Brooke's checks for several years before 1977 said they could not recall seeing any large checks he made out to himself.

In documents presented by Brooke to the court in the divorce case last year Brooke listed his expenses for food at $46.15 per week. In the documents Brooke said he rarely ate out. He lists additional out-of-pocket expenses for about another $35 per week.

An aide to Brooke said this week that the senator's personal expenses were "very low." Brooke, said the aide, "never carries cash around in his pocket. Nobody does these days."

Asked where the money came from for Brooke's food, the aide said, "He eats with his mother almost everyday."