eight
Vertex, have
six
A face, every face is.
rectangular
Shape can be divided into
three
Groups, the shape and size of the surface in each group are
identical
, the cuboid has
12
Rib, can be divided into
three
Groups, the middle edge of each group
length
Equality;
2. In a cuboid, there are three relationships between edges, namely:
stride
、
parallel
and
Different planes
As shown in the figure, in the rectangular ABCD-EFGH,
1) The side parallel to the side BC is
Edge FG, uh, AD
2) The edge intersecting with the edge BC is
Edge AB, FB
3) The side different from the side BC is
Edge AE, DH, EF, HG
Any two sides of a cuboid have at most
1
A common point,
If two sides have nothing in common, can they be different? Answer: Not necessarily, it may be parallel imports.
3. In a cuboid, there are two relationships between edges and faces, namely:
parallel
and
Vertical/vertical
As shown in the figure, in the rectangular ABCD-EFGH,
1) The surface perpendicular to the edge DH is
ABCD
2) The edge perpendicular to the surface ADHE is
AB，CD，EF，GH
3) The surface parallel to the edge DH is
FBCG ABFE
4) The edge parallel to the surface ADHE is
BC，CG，GF，FB
We can use
plumb line
、
Triangular plate bevel gauge
and
Hinge origami
Check whether the straight line is perpendicular to the plane; can use
plumb line
and
Rectangular paper
Test whether the straight line is parallel to the plane.
4. In a cuboid, there are two relationships between planes, namely:
parallel
and
Vertical/vertical
As shown in the figure, in the rectangular ABCD-EFGH,
1) The surface perpendicular to the surface CDHG is
ADHE、EFGH、FGCB、ABCD
2) The surface parallel to the surface CDHG is
ABEF
We can use
plumb line
、
Triangular plate bevel gauge
and
Hinge origami
To test whether the plane is perpendicular to the plane, you can use
Rectangular pieces of paper check whether the plane is parallel to the plane;