JEE Main 20238 AprilMorning Shift
- Exam
- JEE Main
- Year
- 2023
- Date
- 8 April
- Shift
- Morning Shift
- Subject
- Mathematics
- Chapter
- Vector Algebra
JEE Main 2023 · 8 April · Morning Shift · Mathematics · Vector Algebra
If the points with position vectors α ^ i + 10 ^ j + 13 ^ k , 6 ^ i...
If the points with position vectors \alpha\overset{^}{i} + 10\overset{^}{j} + 13\overset{^}{k}, 6\overset{^}{i} + 11\overset{^}{j} + 11\overset{^}{k}, \dfrac{9}{2}\overset{^}{i} + \beta\overset{^}{j} - 8\overset{^}{k} are collinear, then ${\left(19\alpha - 6\beta\right)}^{2} is equal to
Options
- A
- B
- C
- D
Correct answer
A.
Step-by-step solution
The given position vectors can be written as
Also given that these three points are collinear.
Let us assume that the point divides in the ratio .
Since, are collinear
On applying section formula for co-ordinate we get,
Ratio
Now,
Now similarly,
Hence this is the correct option.