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Three Dimensional Geometry

Question
CBSEENMA12033482

Prove that if a plane has the intercepts a, b, c and is at a distance p units from the origin, then 1 over straight a squared plus 1 over straight b squared plus 1 over straight c squared space equals space 1 over straight p squared.

Solution
The equation of plane with intercepts a, b, c is
straight x over straight a plus straight y over straight b plus straight z over straight c equals space 1 space space space space space space space space or space space space straight x over straight a plus straight y over straight b plus straight z over straight c minus 1 space equals space 0
From the given condition,
                      fraction numerator open vertical bar 0 plus 0 plus 0 minus 1 close vertical bar over denominator square root of begin display style 1 over straight a squared end style plus begin display style 1 over straight b squared end style plus begin display style 1 over straight c squared end style end root end fraction space equals space straight p
rightwards double arrow space space space space space space space space space space space square root of 1 over straight a squared plus 1 over straight b squared plus 1 over straight c squared end root space equals 1 over straight p
rightwards double arrow space space space space space space space space space space 1 over straight a squared plus 1 over straight b squared plus 1 over straight c squared space equals space 1 over straight p squared
which is required condition. 

Some More Questions From Three Dimensional Geometry Chapter

Find the direction cosines of x, y and z-axis.