先去括号,在合并同类项:3(2x2﹣y2)﹣2(3y2﹣2x2).
解:3(2x2﹣y2)﹣2(3y2﹣2x2)
=6x2﹣3y2﹣6y2+4x2
=(6x2+4x2)+(﹣3y2﹣6y2)
=10x2﹣9y2.