Ôn tập Hình học 11. chương 1


.  !"#$%&'()!*+#,-,#.&&(/$
0%!1#2&  &(/$M, N 345%%&(/$M’, N’
%M’N’ = MN.
-,%6,0%,7&8 &(/$%9##%&(/$%9##
:!"#$%&'()%;%<&(/$(=1 (4#%9#%(4#%9#1 
%&%%&1 (*>%9#%(*>%9#?#=1 #=,%#=,?#=1
 %&$#-,%%&$#-,?#=1 (4#%@A%(4#%@A,=,B#-
!6C
 -,,D%/8
 %E% 8@*#$F%9#1,*:,%G
( )
Hv a b
r
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%G
( )
Hv a b
r
 1 $J%(/$K%$J%(/$KLM&*,*
NMM v
=
uuuuur r
OPQ8
v
T
r
C
R/%;,%S&(J8
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SK

Y
VU
Y
H'

WZ


:
VKW!(=8U
Y
ZU[&
'
Y
Z'[
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α
!"#()C
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KZKL:#=,VKHKLWZ
α
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α
C
!6Q`V
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α
W
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cR/%;,%S&(J,7&]&',=%$V&HW(/$KVUH'W1(/$KLVULH'LW:#=,
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α
8
Trong mặt phẳng tọa độ Oxy cho Q
(I,
α
W
1với I(a; b). Khi đó Q
(I,
α
W
biến điểm M (x; y)
thành M’(x’; y’) xác định bởi:



−+−+=
−−−+=
αα
αα
,*MWVMWVN
MWV,*MWVN
byaxby
byaxax
 *F,:d%$TVeHeWU
Y
ZUC,*M
α
'CM

α
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Y
ZUCM
α
['C,*M
α
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:g-!6C8VUh&W
\
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ek
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Y
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Y
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e
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Y
Z!'[V!WC'
e
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Y
Z!CU

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Y
Z!C'
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Y
ZX
VH\W
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n- (b#>#%kM^k Vk meW  $j,F(/$K1%
,F(/$KL1LM&*,*KLLZkKC
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α
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ee
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α
o
1
(b#>#%$T1%kM^!1#=,
α
#=, 1 (/$K%K
Y
M&*,*8
TK
Y
Z!CTK
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α

W
VTK1TK
Y
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α
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α
W
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α
W
 
α
Ze
e
1(b#># %:E%<X
VTH!W
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α
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e
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VTH!W
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%&%%&1 (*>%9#%(*>%9#$(J(45,l:dk Vk %k
M^,7&(b#>#W1 %&$#-,%%&$#-,(b#>#:d%kM^k1 $J%
#=,%#=,,=,B#M^(*1 (4#%@A-!6g%(4#%@A,=-
!6g
Y

Z!CgHT
Y
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α
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(b#># '%!&C
RRrs
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V\H Wv = −
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