JEE Main202315 Apr 2023Morning ShiftMathematicsThree Dimensional GeometryActual
Let S be the set of all values of λ , for which the shortest distance between the lines x - λ 0 = y - 3 4 = z + 6 1 and x + λ 3 = y - 4 = z - 6 0 is 13 . Then 8 ∑ λ ∈ S λ is equal to
Options
- A306
- B304
- C308
- D302
Correct answer
A. 306
Step-by-step solution
The given lines are x - λ 0 = y - 3 4 = z + 6 1 and x + λ 3 = y - 4 = z - 6 0 We know that the shortest distance between two lines is d = a → 2 - a → 1 · n → 1 × n → 2 n → 1 × n → 2   &   d = 13   given ⇒ n → 1 × n → 2 = i ^ j ^ k ^ 0 4 1 3 - 4 0 = 4 i ^ + 3 j ^ - 12 k ^ Now using the above formula of distance we get, ⇒ ( 2 λ i ^ + 3 j ^ - 12 k ^ ) · ( 4 i ^ + 3 j ^ - 12 k ^ ) 16 + 9 + 144 = 13