The straight lines whose direction cosines are given by `al + bm + cn – InterviewSolution

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1.	The straight lines whose direction cosines are given by `al + bm + cn = 0`,` fmn + gnl +hlm=0`are perpendicular ifA. `(f)/(a)+(g)/(b)+(h)/(c )=1`B. `(f)/(a)+(g)/(b)+(h)/(c )=-1`C. `(f)/(a)+(g)/(b)+(h)/(c )=0`D. `(a)/(f)+(b)/(g)+(c )/(h)=0`
Answer» Correct Answer - C

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