求3x方-2{x-5[x-3(x-2x方)-3(x方-2x)]-(x-1)}的值,其中x=2
来源:学生作业帮助网 编辑:作业帮 时间:2024/06/27 12:04:52
![求3x方-2{x-5[x-3(x-2x方)-3(x方-2x)]-(x-1)}的值,其中x=2](/uploads/image/z/5912881-25-1.jpg?t=%E6%B1%823x%E6%96%B9-2%7Bx-5%5Bx-3%28x-2x%E6%96%B9%29-3%28x%E6%96%B9-2x%29%5D-%28x-1%29%7D%E7%9A%84%E5%80%BC%2C%E5%85%B6%E4%B8%ADx%3D2)
求3x方-2{x-5[x-3(x-2x方)-3(x方-2x)]-(x-1)}的值,其中x=2
求3x方-2{x-5[x-3(x-2x方)-3(x方-2x)]-(x-1)}的值,其中x=2
求3x方-2{x-5[x-3(x-2x方)-3(x方-2x)]-(x-1)}的值,其中x=2
原式=3x²-2{x-5[x-3(x-2x²)-3(x²-2x)]-(x-1)}
=3x²-2[x-5(x-3x+6x²-3x²+6x)-x+1]
=3x²-2(x-5x+15x-30x²+15x²-30x-x+1)
=3x²-2x+10x-30x+60x²-30x²+60x+2x-2
=(3x²+60x²-30x²)+(-2x+10x-30x+60x+2x)-2
=33x²+40x-2
当x=2时
原式=33×2²+40×2-2
=33×4+80-2
=132+80-2
=210