问题
解答题
先化简,再求值:(x+1-
|
答案
原式=(
-x2-1 x-1
)÷15 x-1 x(x-4) x(x-1)
=
÷x2-16 x-1 x-4 x-1
=
•(x+4)(x-4) x-1 x-1 x-4
=x+4;
当x=
-4时,原式=3
-4+4=3
.3
先化简,再求值:(x+1-
|
原式=(
-x2-1 x-1
)÷15 x-1 x(x-4) x(x-1)
=
÷x2-16 x-1 x-4 x-1
=
•(x+4)(x-4) x-1 x-1 x-4
=x+4;
当x=
-4时,原式=3
-4+4=3
.3