What are the DRs of vectors parallel to (2, -1, 1) and (3, 4, -1)?
(1, 5, -2)
(-2, -5, 2)
(-1, 5, 2)
(-1, -5, -2)
The correct option is A.
Explanation of the correct option: -
Leta,bandcbethedirectionvectorsofthevectorthatisperpendiculartothevectorshavingdirectionratiosas(2,-1,1)&(3,4,-1).So,2a-b+c=0&3a+4b-c=0=(3-2),(4+1),(-1-1)=(1,5,-2)=(a,b,c)Therefore,(a,b,c)=(1,5,-2)
Explanation of the incorrect options: -
Option B: -
Option C: -
Option D: -
Hence, the DRs vectors parallel to the (2,-1,1) and (3,4,-1) is (1,5,-2)