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大题01三角函数、三角恒等变换与解三角形(8大题型)(原卷版)

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题型四 :解三角形中三线问题
      
      
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sin
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a
A
b
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b
¹
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题型五:三角形中图形类边长及范围问题
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A
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a
C
c
A
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2
a
b b
c
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a
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n
n
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n
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1
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1
1
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c
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n
n
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a
b
C
c
-
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3,
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a
b
D
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4
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1
3
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题型七:解三角形中内切圆、外接圆问题
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ABC
V
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c,º
2
2
2
1
3
a
b
c
-
=
.
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ABC
V
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2
1
6
S
c
=
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(2)k tan
3
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,
ABC
V
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6
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ABC
V
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V
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sin
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a
c
B
b
C
-
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.
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ģr
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7
b =
,
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r
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sin
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c
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A
a
 M.
      
      
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V
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2
2
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sin
1
A
B
C
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+
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V
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2
2
2
2
2
4
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c
B
a
b
c
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-
-
 ¬
      
      
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,
30
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2
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120
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BC
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6
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2
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