The shortest distance between the lines x-41= y-32= z-2-3 and x+22= y-64= z-5-5 is :
- 5 66
- 2 5
- 3 5
- 4 5
Answer
(3) 3 5
Solution
Line 1: a1=4 i+3 j+2 k, b1= i+2 j-3 k
Line 2: a2=-2 i+6 j+5 k, b2=2 i+4 j-5 k
b1 b2= vmatrix i & j & k\ 1 & 2 & -3\ 2 & 4 & -5 vmatrix=2 i- j+0 k
| b1 b2 |= 5
a2- a1=-6 i+3 j+3 k
SD = | ( a2- a1 ) ( b1 b2 ) | | b1 b2 |= |-12-3+0| 5
SD = 15 5=3 5
Answer: (3)