question_answer

The two lines \[x=ay\,+b,\,\,z=cy+d\] and\[x=a'\,y+b',\,z=c'\,y+d'\] will be perpendicular, if and only if     AIEEE  Solved  Paper-2003

A) \[aa'+bb'+cc'+1=0\]

B)       \[aa'+bb'+cc'=0\]

C) \[(a+a')\,(b+b')+(c+c')=0\]

D) \[aa'+cc'+1=0\]   

Correct Answer: D

Solution :

Given equations of the lines are                                             ,                                    ... (i) and            ,                          ,                           ? (ii) Eqs. (i) and (ii) will be perpendicular to each other, if