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> 先化简,再求值:x2-2xx2-4÷(x-2-2x-4x+2),其中x满足x2-5x-6=0.-数学
先化简,再求值:x2-2xx2-4÷(x-2-2x-4x+2),其中x满足x2-5x-6=0.-数学
题目简介
先化简,再求值:x2-2xx2-4÷(x-2-2x-4x+2),其中x满足x2-5x-6=0.-数学
题目详情
先化简,再求值:
x
2
-2x
x
2
-4
÷(x-2-
2x-4
x+2
)
,其中x满足x
2
-5x-6=0.
题型:解答题
难度:中档
来源:不详
答案
原式=
x(x-2)
(x+2)(x-2)
÷
x
2
-4-2x+4
x+2
=
class="stub"x
x+2
•
class="stub"x+2
x(x-2)
=
class="stub"1
x-2
,
∵x满足x2-5x-6=0,即(x-6)(x+1)=0,
∴x1=6,x2=-1,
当x=6时,原式=
class="stub"1
4
;当x=-1时,原式=-
class="stub"1
3
.
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题目简介
先化简,再求值:x2-2xx2-4÷(x-2-2x-4x+2),其中x满足x2-5x-6=0.-数学
题目详情
答案
∵x满足x2-5x-6=0,即(x-6)(x+1)=0,
∴x1=6,x2=-1,
当x=6时,原式=