3x²-【5x-(0.5x-3)+2x²】(其中x=-4)
来源:学生作业帮助网 编辑:作业帮 时间:2024/06/27 04:55:33
![3x²-【5x-(0.5x-3)+2x²】(其中x=-4)](/uploads/image/z/380038-22-8.jpg?t=3x%26%23178%3B-%E3%80%905x-%EF%BC%880.5x-3%EF%BC%89%2B2x%26%23178%3B%E3%80%91%EF%BC%88%E5%85%B6%E4%B8%ADx%3D-4%EF%BC%89)
3x²-【5x-(0.5x-3)+2x²】(其中x=-4)
3x²-【5x-(0.5x-3)+2x²】(其中x=-4)
3x²-【5x-(0.5x-3)+2x²】(其中x=-4)
原式=3x²-5x+0.5x-3-2x²
=x²-4.5x-3
当x=-4时
x²-4.5x-3
=(-4)²-4.5×(-4)-3
=16+18-3
=31
3x²-【5x-(0.5x-3)+2x²】
=3x²-(5x-0.5x+3+2x²)
=3x²-2x²-4.5x-3
=x²-4.5x-3
=(-4)²+4.5x4-3
=16+18-3
=-1
3x²-【5x-(0.5x-3)+2x²】
=3x²-(5x-0.5x+3+2x²)
=3x²-(4.5x+3+2x²)
=3x²-4.5x-3-2x²
=x²-4.5x-3