分解因式题!Help me!
来源:百度知道 编辑:UC知道 时间:2024/06/08 12:07:12
1.ab(a+b)^2-(a+b)^2+1
2.x^2+xy-6y^2+x+13y-6
(看的明白吧!x^2既是x的平方)
帮忙算一算,写出步骤,万分感激!
2.x^2+xy-6y^2+x+13y-6
(看的明白吧!x^2既是x的平方)
帮忙算一算,写出步骤,万分感激!
1.AB(A+B)^2-(A+B)^2 +1
=(AB-1)(A+B)^2+1
=(AB-1)A^2+(AB-1)B^2+2AB(AB-1)+1
=(AB-1)A^2+(AB-1)B^2+2(AB)^2-2AB+1
=(AB-1)A^2+(AB-1)B^2+(AB)^2+(AB)^2-2AB+1
=(AB-1)A^2+(AB-1)B^2+(AB)^2+(AB^2-2AB+1)
=(AB-1)A^2+(AB-1)B^2+(AB)^2+(AB-1)^2
=[(AB-1)A^2+(AB)^2]+[(AB-1)B^2+(AB-1)^2]
=A^2[(AB-1)+B^2]+(AB-1)*[(AB-1)+B^2]
=[A^2+(AB-1)]*[B^2+(AB-1)]
2.x^2+xy-6y^2+x+13y-6
x^2+xy-6y=[x+3y][x-2y]
所以设原式=[x+3y+m][x-2y+n]
=[x+3y][x-2y]+n[x+3y]+m[x-2y]+mn
=[x+3y][x-2y]+[n+m]x+[3n-2m]y+mn
则有:
m+n=1
3n-2m=13
mn=-6
m=-2
n=3
所以原式=[x+3y-2][x-2y+3]