Angle between space diagonal in a cube?
Wondering if the angle between two space diagonals of a cube, which are lying in one plane have always the same angle. 
I have now calculated a lot but become somehow confused and cant get a definite answer.
Angle between space diagonal in a cube?
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Wondering if the angle between two space diagonals of a cube, which are lying in one plane have always the same angle. 
I have now calculated a lot but become somehow confused and cant get a definite answer.