2019-2020
瀛﹀勾鏁板涓�冩ā鎷熻瘯鍗?/p>
涓�銆侀�夋嫨棰?/p>
1
锛庡鍥撅紝宸茬煡鈭?/p>
ABC=
鈭?/p>
BAD
锛屾坊鍔犱笅鍒楁潯浠惰繕涓嶈兘鍒ゅ畾鈻?/p>
ABC
鈮屸柍
BAD
鐨勬槸锛?/p>
锛?/p>
A.
鈭?/p>
C=
鈭?/p>
D
B.
鈭?/p>
CAB=
鈭?/p>
DBA
C.AC=BD
D.BC=AD
2
锛庡鍥撅紝鍦?/p>
Rt
鈻?/p>
ABC
涓紝鈭?/p>
ACB
锛?0掳锛屸垹
A
锛?0掳锛?/p>
AC
锛?/p>
2
锛?/p>
D
鏄?/p>
AB
杈逛笂涓�涓姩鐐癸紙涓嶄笌鐐?/p>
A
銆?/p>
B
閲?/p>
鍚堬級锛?/p>
E
鏄?/p>
BC
杈逛笂涓�鐐癸紝涓斺垹
CDE
锛?0掳锛庤
AD
锛?/p>
x
锛?/p>
BE
锛?/p>
y
锛屽垯涓嬪垪鍥捐薄涓紝鑳借〃绀?/p>
y
涓?/p>
x
鐨勫嚱鏁板叧绯?/p>
鐨勫浘璞″ぇ鑷存槸锛?/p>
锛?/p>
A
锛?/p>
B
锛?/p>
C
锛?
D
锛?/p>
3
锛庡鍥?/p>
,
鈻?/p>
ABC
涓?/p>
,BD
骞冲垎鈭?/p>
ABC,BC
鐨勫瀭鐩村钩鍒嗙嚎浜?/p>
BC
浜庣偣
E,
浜?/p>
BD
浜庣偣
F,
杩炴帴
CF.
鑻モ垹
ACF=2
鈭?/p>
ABD,
鈭?/p>
BFC=132掳,鍒?/p>
cosA
鐨勫�间负
(
)
A
锛?
1
2
B
锛?
2
2
C
锛?
3
2
D
锛?
3
3
4
锛庝笅鍒楄繍绠楁纭殑鏄紙
锛?/p>
A.a
5
锕?/p>
a
3
锛?/p>
a
2
B.6x
3
y
2
梅锛堬梗
3x
锛?/p>
2
锛?/p>
2xy
2
C.
2
2
1
2a
2a
飥?/p>
飥?
D.
锛堬梗
2a
锛?/p>
3
锛濓梗
8a
3
5
锛庝笅鍒楄绠楃粨鏋滄纭殑鏄紙
锛?/p>
A.
锛堬梗
a
锛?/p>
2
鈥
6
锛濓梗
a
8
B.
锛?/p>
m
锕?/p>
n
锛夛紙
m
2
+mn+n
2
锛夛紳
m
3
锕?/p>
n
3
C.
锛堬梗
2b
2
锛?/p>
3
锛濓梗
6b
6
D.