Methane Dot Products

Problem

In a methane molecule CH4\mathrm{CH}_4, the four hydrogen atoms sit at the vertices H1,H2,H3,H4H_1, H_2, H_3, H_4 of a regular tetrahedron with edge length 11, and the carbon atom sits at the center C0C_0. Find

1i<j4C0HiC0Hj.\sum_{1 \leqslant i < j \leqslant 4} \overrightarrow{C_0H_i} \cdot \overrightarrow{C_0H_j}.

Answer

Solution

Difficulty5/10
TopicsPolarization Identity, solid geometry, Symmetry, vectors

Whiteboard

Your sketch is saved only in this browser. To share it, export your drawing as an image (whiteboard menu → Export as → PNG), then upload that image in the comments below.

Discussion

Ask questions, share alternate solutions, and use LaTeX freely.

0 comments
Log in to join the discussion.

No comments yet.