Class 12MathematicsTHREE DIMENSIONAL GEOMETRYSystem of co-ordinates, Direction cosines and direction ratios, Projection
EasyIf $< a, b, c >$ and $< a', b', c' >$ are the direction ratios of two perpendicular lines,then which of the following is true?
- A$a/a' = b/b' = c/c'$
- B$aa' + bb' + cc' = 0$
- C$aa' + bb' + cc' = 1$
- DNone of these
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