问题
解答题
先化简,后求值:(
|
答案
原式=
•3x(x+1)-x(x-1) (x+1)(x-1)
=(x+1)(x-1) 2x
•2x(x+2) (x+1)(x-1)
=x+2,(x+1)(x-1) 2x
当x=
-2时,原式=3
-2+2=3
.3
先化简,后求值:(
|
原式=
•3x(x+1)-x(x-1) (x+1)(x-1)
=(x+1)(x-1) 2x
•2x(x+2) (x+1)(x-1)
=x+2,(x+1)(x-1) 2x
当x=
-2时,原式=3
-2+2=3
.3