AUSTIN, TEX., JULY 21 -- The Texas legislature, ending a seven-month struggle with Gov. Bill Clements (R) over how to balance a state budget decimated by declining oil revenues and a depressed economy, today gave final approval to a record $5.7 billion tax increase.

More than one-third of the House, mostly Republicans, refused to go along with the compromise hammered out between Democratic leaders of the legislature and Clements, who had vowed in last year's election he would not raise taxes but ended up agreeing to the largest increase in the state's history.

The tax bill, part of a broad budget package, calls for an increase in the state sales tax from 5.25 to 6 cents on the dollar and a broadening of its base. It also raises the corporate franchise tax and the motor vehicle sales tax, and imposes a $110 annual fee on professionals. The bill also makes permanent a 15-cent-per-gallon gasoline tax enacted last year as a temporary measure.

The $38.3 billion two-year budget is 4 percent higher than the 1986-87 two-year budget, according to the Texas Legislative Budget Board. Legislators said the increase allows state services to keep pace with population growth and inflation and gives a $392 million boost to higher education. The state currently ranks near the bottom nationally in per capita public welfare expenditures and 13th in per capita higher education spending.

Education spending was the top priority of Lt. Gov. Bill Hobby (D), who heads the Democrat-controlled state Senate. Hobby, the leading proponent of higher taxes, clashed with Clements all year over fiscal priorities, a fight that prevented the legislature from approving the budget during its regular biennial session that ended in June.

The session had an ironic ending for Clements, who heard praise from Democratic opponents and criticism from fellow Republicans.

State Sen. Ray Farabee (D) said the governor is "simply willing to take the heat from his own party and those who want no {new} taxes. I applaud him for that."

Angry Republicans, however, urged Clements to apologize for what they said was a betrayal of his party. Clements' action "certainly has blurred the distinction between the Republican approach and the Democrat approach," state Rep. Geral Geistweidt (R) said today.

Both Hobby and Clements gave in on their original budgets. Hobby came down from a $40 billion budget, while the governor moved up from his $36.9 billion proposal. Clements' staff sought to portray his reversal on taxes as the culmination of a shrewd negotiating stance. As part of his deal with the Democratic leadership, the governor also obtained a bill that enhances executive authority over the budget.