α
=
4
.
4
7
2
1
4
β
=
4
.
4
7
2
1
4
γ
=
4
.
0
0
0
0
0
c
o
s
(
A
)
=
0
.
4
4
7
2
1
2
α
=
2
0
.
0
0
0
0
0
-
2
β
γ
c
o
s
(
A
)
+
2
β
+
2
γ
=
2
0
.
0
0
0
0
0