合并同类项 3a-2a^2+4-3a^2+a xy+2xy-3x^2-3xy+x^2 5a^2b-3ab-4ab^2+7ab-2ab^2 4-2xy+7xy-15+xy 只需两步

来源:学生作业帮助网 编辑:作业帮 时间:2024/05/11 18:34:05
合并同类项 3a-2a^2+4-3a^2+a xy+2xy-3x^2-3xy+x^2 5a^2b-3ab-4ab^2+7ab-2ab^2 4-2xy+7xy-15+xy 只需两步

合并同类项 3a-2a^2+4-3a^2+a xy+2xy-3x^2-3xy+x^2 5a^2b-3ab-4ab^2+7ab-2ab^2 4-2xy+7xy-15+xy 只需两步
合并同类项 3a-2a^2+4-3a^2+a xy+2xy-3x^2-3xy+x^2 5a^2b-3ab-4ab^2+7ab-2ab^2 4-2xy+7xy-15+xy
只需两步

合并同类项 3a-2a^2+4-3a^2+a xy+2xy-3x^2-3xy+x^2 5a^2b-3ab-4ab^2+7ab-2ab^2 4-2xy+7xy-15+xy 只需两步
3a-2a^2+4-3a^2+a
=(3+1)a+(-2-3)a²+4
=4a-5a²+4
xy+2xy-3x^2-3xy+x^2
=(1+2-3)xy+(-3+1)x²
=-2x²
5a^2b-3ab-4ab^2+7ab-2ab^2
=5a²b+(-3+7)ab+(-4-2)ab²
=5a²b+4ab-6ab²
4-2xy+7xy-15+xy
=(4-15)+(-2+7+1)xy
=-11+6xy