解方程:(x-5)(x^2-x+1)-x(2^2-6x)=19

来源:学生作业帮助网 编辑:作业帮 时间:2024/04/29 03:31:16
解方程:(x-5)(x^2-x+1)-x(2^2-6x)=19

解方程:(x-5)(x^2-x+1)-x(2^2-6x)=19
解方程:(x-5)(x^2-x+1)-x(2^2-6x)=19

解方程:(x-5)(x^2-x+1)-x(2^2-6x)=19
方程是不是:(x-5)(x^2-x+1)-x(x^2-6x)=19
(x-5)(x^2-x+1)-x^2(x-6)=19
(x-5)(x^2-x+1)-x^2[(x-5)-1]=19
(x-5)(x^2-x+1-x^2)+x^2=19
(x-5)(-x+1)+x^2=19
-x^2+6x-5+x^2=19
6x=24
x=4
或者全部展开:
x^3-x^2+x-5x^2+5x-5-x^3+6x^2=19
立方项和平方项全部消去:6x=24
x=4

(x-5)(x^2-x+1)-x^2(x-6)=19
(x-5)(x^2-x+1)-x^2[(x-5)-1]=19
(x-5)(x^2-x+1-x^2)+x^2=19
(x-5)(-x+1)+x^2=19
-x^2+6x-5+x^2=19
6x=24
x=4