If the line passes through the points P (6 ,-1 ,2 ), Q (8 ,-7 ,2 ) and R (5 ,2 ,4 ) then value of is

Question

Accepted Answer

Correct answer: C. (c) : Let a and b be the position vectors of the points P (6 ,-1 ,2 ) and R (5 ,2 ,4 ). Thus, a=6i-j+2k ,b=5i+2j+4k Now, b-a=-i+3j+2k ∴ Vector equation of the line passing through P and R is r=a+ b ⇒r= (6i-j+2k )+ (-i+3j+2k ) ⇒r= (6- )i+ (3 -1 )j+ (2 +2 )k This equation passes through Q (8 ,-7 ,2 ). ∴8i-7j+2 k= (6- )i+ (3 -1 )j+ (2 +2 )k ⇒6- =8 ,3 -1=-7 ,2 +2=2 ⇒ =-2 ⇒2 (-2 )+2=2 ⇒ =-1

$If the line passes through the points P (6, - 1, 2), Q (8, - 7, 2 λ) and R (5, 2, 4) then value of λ is$

Solution

More Three-Dimensional Geometry PYQs