问题
解答题
先化简,再求值:(
|
答案
原式=[
-(x+1)]÷3 x-1 x-2 x(x-1)
=
•3-(x2-1) x-1 x(x-1) x-2
=-(x+2)(x-2)•x x-2
=-x2-2x;
x是方程x2+x=0的解,可得x=0或-1;而当x=0时,原式无意义,故x=-1.
当x=-1时,原式=1.
先化简,再求值:(
|
原式=[
-(x+1)]÷3 x-1 x-2 x(x-1)
=
•3-(x2-1) x-1 x(x-1) x-2
=-(x+2)(x-2)•x x-2
=-x2-2x;
x是方程x2+x=0的解,可得x=0或-1;而当x=0时,原式无意义,故x=-1.
当x=-1时,原式=1.