xcxd.net
当前位置:首页 >> 先化简,再求值:(1%1x?1)÷x2?4x+4x2?1,其中,x满足%2<x≤2且x为整数 >>

先化简,再求值:(1%1x?1)÷x2?4x+4x2?1,其中,x满足%2<x≤2且x为整数

原式=(3?x)(x?1)?1 x?1 ?(x?1)(x+1) x?2 =?x2+4x?4 x?1 *(x+1)(x?1) x?2 =?(x?2)2 x?1 *(x+1)(x?1) x?2 =-(x-2)(x+1)=-x2+x+2.,解不等式组x+3≤4① x 2 ?3由①得x≤1,由②得x>-2,不等式的解集为-2当x=-1时,原式无意义;当x=0时,原式=2.

原式= 1 x+2 - (x?2)2 x(x?1) ÷ (x+1)(x?1)?3 x?1 = 1 x+2 - (x?2)2 x(x?1) ? x?1 (x+2)(x?2) = 1 x+2 - x?2 x(x+2) = 2 x2+2x 解不等式 2x?5 3 -2∵x是不等式式 2x?5 3 ∴x=-1,∴原式= 2 (?1)2+2*(?1) =-2.

解:原式=[3/(x+1)-(x-1)]*(x+1)/(x-4x+4)=(3-x+1)/(x+1)*(x+1)/(x-2)=-(x+2)(x-2)/(x+1)*(x+1)/(x-2)=-(x+2)/(x-2)因为x-2=0,x+1=0所以x不等于2,-1所以x=0时原式=-(0+2)/(0-2) =1

解:(x-4x+4)/(x-4)-(x+2)/(x-2)=(x-2)/(x-2)(x+2)-(x+2)/(x-2)=(x-2)-(x+2)/(x+2)(x-2)=(x-4x+4-x-4x-4)/(x+2)(x-2)=-8x/(x-4)=-8√2/[(√2)-4]=4√2[(x-1)/3x-(x+1)/x)]*x/(x-1)=[(x-1)/3x-(x+1)/x)]*x/(x-1)(x+1)=[(x-1-3x-3)/3x]*x/(x-1)(x+1)=[(-2x-4)/3x]*x/(x-1)(x+1)=(-2x-4)/(3x-3)=(-2*2-4)/(3*2-3)=-8/9

原式=x-2x-1(x+1)(x-1)(x-2)2=x+1x-2.x满足-2≤x≤2且为整数,若使分式有意义,x只能取0,-2.∴当x=0时,原式=-12(或:当x=-2时,原式=14).

解:(3x+4/x2-1-2/x-1)÷x+2/x2-2x+1=[3x+4/(x+1)(x-1)-2(x+1)/(x+1)(x-1)](x-1)/2x+2=3x+4-2x-2/(x+1)(x-1)(x-1)2/x+2=x+2/(x+1)(x-1)(x-1)2/x+2=x-1/x+1,又x+4>0①2x+5由①解得:x>-4,由②解得:x∴不等式组的解集为-4其整数解为-3,当x=-3时,原式=-3-1-3+1=2.

原式= x?4 (x+1)(x?1) * (x+1)2 (x?4)(x+1) + 1 x?1 = 1 x?1 + 1 x?1 = 2 x?1 当x=5时,原式= 2 5?1 = 1 2 .

(1+ 1 x )÷ x2?1 x2 ,= x+1 x ? x2 (x+1)(x?1) ,= x x?1 .当x是满足-2而要使原分式有意义,x≠±1,且x≠0,即x=2,当x=2时,原式= 2 2?1 =2.

(1+1x)÷x21x2,=x+1xx2(x+1)(x1),=xx1.当x是满足-2

原式=(x2)2x(x2)÷x24x…3分=(x2)2x(x2)x(x+2)(x2)=1x+2…5分∵-5

相关文档
网站首页 | 网站地图
All rights reserved Powered by www.xcxd.net
copyright ©right 2010-2021。
内容来自网络,如有侵犯请联系客服。zhit325@qq.com