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Shear unit cube w.r.t. yz plane

Short answer

Shearing with respect to the yz plane fixes x and displaces y and z by 2x. Original unit cube corners (0,0,0) to (1,1,1) become (0,0,0), (0,0,1), (0,1,0), (0,1,1), (1,2,2), (1,2,3), (1,3,2), (1,3,3).

A unit length cube with diagonal passing through (0,0,0) and (1,1,1) is sheared with respect to yz plane with the shear constants = 2 in both directions. Obtain the coordinates of all the corners of the cube after shearing.

Assumption: shear "with respect to the yz plane" keeps the x-coordinate fixed (the yz plane, x = 0, does not move). The y and z coordinates are displaced in proportion to x with shear constants sh_y = sh_z = 2. The unit cube has corners from (0,0,0) to (1,1,1).

Equations: x' = x, y' = y + 2x, z' = z + 2x

| x' |   | 1 0 0 0 | | x |
| y' | = | 2 1 0 0 | | y |
| z' |   | 2 0 1 0 | | z |
| 1  |   | 0 0 0 1 | | 1 |
Corner(x, y, z)y + 2xz + 2xNew corner
A(0,0,0)00(0,0,0)
B(0,0,1)01(0,0,1)
C(0,1,0)10(0,1,0)
D(0,1,1)11(0,1,1)
E(1,0,0)22(1,2,2)
F(1,0,1)23(1,2,3)
G(1,1,0)32(1,3,2)
H(1,1,1)33(1,3,3)

The face x = 0 stays in place and the face x = 1 slides by 2 units in both y and z.

Answer: (0,0,0), (0,0,1), (0,1,0), (0,1,1), (1,2,2), (1,2,3), (1,3,2), (1,3,3).

✓ Answer checked by Claude Opus 5.5 (high effort)

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