问题
解答题
当x=-
|
答案
原式=
×3x(x+1)-x(x-1) (x-1)(x+1)
,(x+1)(x-1) x
=
×3x2+3x-x2+x (x+1)(x-1)
,(x+1)(x-1) x
=2x+4,
当x=-
时,原式=2×(-1 3
)+4,1 3
=
.10 3
当x=-
|
原式=
×3x(x+1)-x(x-1) (x-1)(x+1)
,(x+1)(x-1) x
=
×3x2+3x-x2+x (x+1)(x-1)
,(x+1)(x-1) x
=2x+4,
当x=-
时,原式=2×(-1 3
)+4,1 3
=
.10 3