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在平行六面体ABCD-A1B1C1D1中,AB=1,AD=2,AA1=3,∠BAD=60°,∠BAA1=∠DAA1=90°,则AC1的长为()A.25B.4C.5D.26

题目详情
在平行六面体ABCD-A1B1C1D1中,AB=1,AD=2,AA1=3,∠BAD=60°,∠BAA1=∠DAA1=90°,则AC1的长为(  )

A.2
5

B.4
C.5
D.2
6
11111111

2
5

B.4
C.5
D.2
6
5
5
5


2
6
6
6
6
▼优质解答
答案和解析
在平行六面体ABCD-A11B11C11D11中,
∵AB=1,AD=2,AA11=3∠BAD=60°,∠BAA11=∠DAA11=90°,
AC1
=
AB
+
BC
+
CC1

AC1
2=(
AB
+
BC
+
CC1
2
=
AB
2+ 
BC
2+
CC1
2+2
AB
BC
+2
AB
CC1
+2
BC
CC1

=1+4+9+2×1×2×cos60°+0+0
=16,
|
AC1
|=4.
故选B.
AC1
AC1AC1AC11=
AB
+
BC
+
CC1

AC1
2=(
AB
+
BC
+
CC1
2
=
AB
2+ 
BC
2+
CC1
2+2
AB
BC
+2
AB
CC1
+2
BC
CC1

=1+4+9+2×1×2×cos60°+0+0
=16,
|
AC1
|=4.
故选B.
AB
ABABAB+
BC
BCBCBC+
CC1
CC1CC1CC11,
AC1
2=(
AB
+
BC
+
CC1
2
=
AB
2+ 
BC
2+
CC1
2+2
AB
BC
+2
AB
CC1
+2
BC
CC1

=1+4+9+2×1×2×cos60°+0+0
=16,
|
AC1
|=4.
故选B.
AC1
AC1AC1AC1122=(
AB
+
BC
+
CC1
2
=
AB
2+ 
BC
2+
CC1
2+2
AB
BC
+2
AB
CC1
+2
BC
CC1

=1+4+9+2×1×2×cos60°+0+0
=16,
|
AC1
|=4.
故选B.
AB
ABABAB+
BC
BCBCBC+
CC1
CC1CC1CC11)22
=
AB
2+ 
BC
2+
CC1
2+2
AB
BC
+2
AB
CC1
+2
BC
CC1

=1+4+9+2×1×2×cos60°+0+0
=16,
|
AC1
|=4.
故选B.
AB
ABABAB2+ 
BC
2+
CC1
2+2
AB
BC
+2
AB
CC1
+2
BC
CC1

=1+4+9+2×1×2×cos60°+0+0
=16,
|
AC1
|=4.
故选B.
2+ 
BC
BCBCBC2+
CC1
2+2
AB
BC
+2
AB
CC1
+2
BC
CC1

=1+4+9+2×1×2×cos60°+0+0
=16,
|
AC1
|=4.
故选B.
2+
CC1
CC1CC1CC112+2
AB
BC
+2
AB
CC1
+2
BC
CC1

=1+4+9+2×1×2×cos60°+0+0
=16,
|
AC1
|=4.
故选B.
2+2
AB
BC
+2
AB
CC1
+2
BC
CC1

=1+4+9+2×1×2×cos60°+0+0
=16,
|
AC1
|=4.
故选B.
2
AB
ABABAB•
BC
BCBCBC+2
AB
CC1
+2
BC
CC1

=1+4+9+2×1×2×cos60°+0+0
=16,
|
AC1
|=4.
故选B.
AB
ABABAB•
CC1
CC1CC1CC11+2
BC
CC1

=1+4+9+2×1×2×cos60°+0+0
=16,
|
AC1
|=4.
故选B.
BC
BCBCBC•
CC1
CC1CC1CC11
=1+4+9+2×1×2×cos60°+0+0
=16,
|
AC1
|=4.
故选B.
|
AC1
AC1AC1AC11|=4.
故选B.