内容正文:
!12"# 16451+30(2)
【
!"#$
】
V4TUL5NIOWX=
1. 10.52 �;)*#& (C )
A.10.52=102+0.52
B.10.52=(11+0.5)(11-0.5)
C.10.52=102+2×10×0.5+0.52
D.10.52=112-11×0.5+0.52
2.!":
(1)9992;
!
:9992 =(1000-1)2
=1000000-2000+1
=998001;
(2)1022;
!
:1022 =(100+2)2
=10000+400+4
=10404;
(3)1.23452+0.76552+2.469×0.7655.
!
:
"#=1.23452+2×1.2345×0.7655+0.76552
=(1.2345+0.7655)2
=4.
【
!"#,
】
TUL5NI-L5MNI)34
3.'(H")*#& (B )
A.犪2-犪4=犪8 B.2犪+3犪=5犪
C.(狓-2)2=狓2-4 D.(狓-2)(狓-3)=狓2-6
4.!":
(1)(2犪-3犫)2-2(2犪+3犫)(2犪-3犫)+(2犪+3犫)2;
!
:
"#=[(2犪-3犫)-(2犪+3犫)]2
=36犫2;
(2)(3狓+2狔-4)(2狔-3狓+4);
!
:
"#=(2狔)
2-(3狓-4)2;
=4狔
2-9狓2+24狓-16;
(3)(犿-狀-3)2;
!
:
"#=(犿-狀)2-2×(犿-狀)×3+32
=犿2+狀2+9-2犿狀+6狀-6犿;
(4)(犪+3)2(犪2-6犪+9).
!
:
"#=(犪+3)2 (犪-3)2
=(犪2-9)2
=犪4-18犪2+81.
5.YZ[:(狓+
1
2
)
2
-(狓+1)(狓-1)=1.
!
:
$"jk
,
'狓2+狓+
1
4
-狓2+1=1,
®C
、̄
°ABC
,
'狓=-
1
4
.
【
!"#2
】
Y5+
6.BC(狓+狔)
2=7,(狓-狔)
2=3,0狓2+狔
2=
(D )
A.58 B.29 C.10 D.5
7.V�,h7)Z;pßüw.犪、犫,V%犪+犫=7,犪犫=
12,0���ü#+". (D )
A.25 B.12.5 C.13 D.6.5
8.(1)�狓+狔=5,狓狔=-12�,=�9<
狓2-狓狔+狔
2
#D.
!
:∵狓+狔=5,狓狔=-12,
∴狓2-狓狔+狔
2=(狓+狔)
2-3狓狔
=52-3×(-12)=61.
(2)BC:狓+
1
狓
=3,=狓4+
1
狓4
#D.
!
:
"#=(狓2+
1
狓2
)
2
-2
=[(狓+
1
狓
)
2
-2]
2
-2
=(32-2)2-2
=47.
·32·
9.(1)V%犕=(狓2+2狓+1)(狓2-2狓+1),犖=
(狓2+狓+1)·(狓2-狓+1),狓<0,WX犕 N
犖 #^pde& (B )
A.犕>犖 B.犕<犖
C.犕=犖 D.�7*E
(2)�9<(狓+2狔)
2-4(狓+2狔-1)#D&
(A )
A.^U��PU� B.pU�
C.PU� D.^U�
10.(1)/狓-狔=3,狓-狕=1,0(2狓-狔-狕)
2+
(狕-狓)2#D& 17 ;
(2)BC犿2-5犿-1=0,02m2-5m+
1
犿2
= 28 ;
(3)/狓[q(狓-3)(狓-1)=5,0(狓-3)2
+(狓-1)2= 14 .
11.V�,@h7)Z;犃,犅,> 犅�§犃 #
��×�§
,
犃,犅 4(�ÓhÔÕG#
)Z;×�¨./�§J�¨?���ü
#+"üw.3J15,0)Z;犃,犅#+
"aJ. 18 .
12.!":
(1)(狓3狀+1)(狓3狀-1)-(狓3狀-1)2;
!
:
"#=狓6狀-1-狓6狀+2狓3狀-1
=2狓3狀-2;
(2)(2狓狀+1)2(-2狓狀+1)2-16(狓狀+1)2(狓狀-1)2.
!
:
"#=[(1+2狓狀)(1-2狓狀)]2-16[(狓狀+1)(狓狀-1)]2
=(1-4狓2狀)2-16(狓2狀-1)2
=1-8狓2狀+16狓4狀-16狓4狀+32狓2狀-16
=24狓2狀-15.
13./犪2+2犫2+2犪犫+4犫+4=0�,=犪犫.
!
:∵犪2+2犫2+2犪犫+4犫+4=0,
∴(犪2+犫2+2犪犫)+(犫2+4犫+4)=0,
�-'
(犪+犫)2+(犫+2)2=0,
±²³´42µg
,犫+2=0,犪+犫=0,
!'犫=-2,犪=2.(犪犫=2-