Opposition exclusion method?
In the perspective view, the opposite faces are not adjacent, so if two adjacent opposite faces appear in the perspective view of the option at the same time, they can be directly excluded. (Judging opposites: two faces separated by a row/column and having a common edge with the separated row/column are opposites. )
Example 1
Analysis 1 plane and 3 planes are separated by 2 columns in the expansion diagram, so they are opposite. The opposition in option A is adjacent and can be excluded. Face 2 and face 5 are separated by column 3, so they are opposite. Option b has antonyms and can be excluded. The 4th and 6th faces are separated by the 2nd row, so they are opposite. There are antonyms in the d option, which can be excluded. So, the answer to this question is C.
Asymmetric central figure positioning method?
Select an asymmetric graphic surface or a non-repeating surface as the reference surface in the option, and observe whether the adjacent surface of the reference surface in the option is consistent with the flat pattern.
Example 2
Look at option A first. Plane A and plane C are opposite, adjacent and exclusive. Option B takes plane C as the reference plane, so the front of item B should be plane B in the development drawing. If it is inconsistent with option B, it is excluded. D option plane b and plane f are opposite, adjacent and exclusive, so the answer to this question is C.
Draw the edge method?
Firstly, a special surface (non-repeating surface and non-central symmetric surface) is determined by combining options. Then, determine the starting point in the surface and draw the edge clockwise. Finally, match the options with the expanded map and eliminate any inconsistencies.
Example 3
First, take the plane C as the reference plane and the right angle point of the black triangle in the plane C as the starting point, and mark 1-4 clockwise. As shown in the figure, side 2 is connected with plane A, and side 3 is connected with plane B. Observing options A, A and C, both sides are connected with side 1. If they are inconsistent with the development diagram, they shall be rejected. Observe that the two sides of options B, B and C are connected with side 4, which is inconsistent with the expanded drawing and excluded. Observe option d. The two sides of B and C are connected with side 3, which are inconsistent with the development drawing, and are excluded. So, the answer to this question is C.
The above three methods need to be combined with the specific characteristics of the expansion diagram, and choose the appropriate way to solve the problem quickly. The majority of candidates need to be familiar with the application of problem-solving methods and do more exercises to apply what they have learned.