- Exam
- JEE Main
- Year
- 2023
- Date
- 10 April
- Shift
- Morning Shift
- Subject
- Mathematics
- Chapter
- Three Dimensional Geometry
JEE Main 2023 · 10 April · Morning Shift · Mathematics · Three Dimensional Geometry
The shortest distance between the lines (x + 2)/(1) = (y)/(- 2) =...
Options
- A
- B
- C
- D
Correct answer
D.
Step-by-step solution
Given,
Now we know that,
Shortest distance between two skew lines is given by,
Now finding, \overset{\to}{{n}_{1}} \times \overset{\to}{{n}_{2}} = \left|\begin{cases}\overset{^}{i} & \overset{^}{j} & \overset{^}{k} \\ 1 & - 2 & 2 \\ 1 & 2 & 0\end{cases}\right|
⇒ \overset{\to}{{n}_{1}} \times \overset{\to}{{n}_{2}} = - 4\overset{^}{i} + 2\overset{^}{j} + 4\overset{^}{k}
And \overset{\to}{{a}_{2}} - \overset{\to}{{a}_{1}} = \left(4\overset{^}{i} + \overset{^}{j} - 3\overset{^}{k} - \left(- 2\overset{^}{i} + 0\overset{^}{j} + 5\overset{^}{k}\right)\right) = 6\overset{^}{i} + \overset{^}{j} - 8\overset{^}{k}
Now putting the value in formula we get,
SD = \left|\dfrac{\left(6\overset{^}{i} + \overset{^}{j} - 8\overset{^}{k}\right)\left(- 4\overset{^}{i} + 2\overset{^}{j} + 4\overset{^}{k}\right)}{\sqrt{16 + 16 + 4}}\right|