（初中数学）先去括号：3x²-[7x-(4x-3)-2x²] 原式

来源：学生作业学帮网编辑：学帮网时间：2024/05/14 02:48:03

3x²-[7x-(4x-3)-2x²]
=3x²-7x+(4x-3)+2x²
= 3x²-7x+4x-3+2x²
=5x²-3x-3

5x²-3x-3

3x²-[7x-(4x-3)-2x²]
= 3x²-7x+4x-3+2x²
=5x²-3x-3

3x²-[7x-(4x-3)-2x²]
=3x²-(7x-4x+3-2x²)
=3x²-(3x+3-2x²)
=3x²-3x-3+2x²
=5x²-3x-3

3x2_[7x-(4x-3)-2x2]=3x2_(4x+3-2x2)=3x2-4x-3+2x2=5x2-4x-3