NTA Abhyas JEE Main2020MathematicsVector AlgebraPractice
Let x → and y → are 2 non-zero and non-collinear vectors, then the largest value of k such that the non-zero vectors k 2 - 5 k + 6 x → + k - 3 y → and 2 x → + 5 y → are collinear is
Options
- A3
- B6
- C12 5
- D- 1
Correct answer
C. 12 5
Step-by-step solution
Let, a → = k 2 - 5 k + 6 x → + k - 3 y → and b → = 2 x → + 5 y → ∵ a → and b → are collinear vectors ⇒ k 2 - 5 k + 6 2 = k - 3 5 ⇒ k = 3 , 12 5 But, for k = 3 , a → = 0 (not possible)