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1.15a^2-[5a-8a^2-(2a^2-a)+9a^2]2.-7x^2+(6x^2-5xy)-2(3y^2+xy-x^2)3.3a^2b-[2ab^2-2(ab-3/2a^2b)+ab]+4ab^2

题目详情
1.15a^2-[5a-8a^2-(2a^2-a)+9a^2]
2.-7x^2+(6x^2-5xy)-2(3y^2+xy-x^2)
3.3a^2b-[2ab^2-2(ab-3/2a^2b)+ab]+4ab^2
▼优质解答
答案和解析
15a^2-[5a-8a^2-(2a^2-a)+9a^2]=15a^2-[5a-8a^2-2a^2+a+9a^2]=15a^2-5a+8a^2+2a^2-a-9a^2=16a^2-5a-7x^2+(6x^2-5xy)-2(3y^2+xy-x^2)=-7x^2+6x^2-5xy-6y^2-2xy+2x^2=-5x^2-7xy3a^2b-[2ab^2-2(ab-3/2a^2b)+ab]+4ab^2 =...