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Show that tha angles between the diagonals of a rectangular parallelopiped having sides a,b and c are `cos^(-1)((|alpha|)/(a^(2)+b^(2)+c^(2)))`, where `alpha=pma^(2)pmb^(2)pmc^(2)and|alpha|!=a^(2)+b^(2)+c^(2)`. Hence find the angle between the diagonals of a cube.

Text Solution

Verified by Experts

The correct Answer is:
`cos^(-1)(1)/(3).`
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