MHT CET202121 Sep 2021Morning ShiftMathematicsThree Dimensional GeometryActual
The distance between parallel lines r =(2 i - j + k )+ (2 i + j - k ) and r =( i - j +2 k )+ (2 i + j -2 k ) is
Options
- A2
- B1 3
- C1 3 units
- D2 3 units
Correct answer
D. 2 3 units
Step-by-step solution
The distance between given parallel lines aligned & = | [( i -2 i )+(- j + j )+(2 k - k )] (2 i + j -2 k ) |2 i + j -2 k | |= | (- i + k ) (2 i + j -2 k ) (2)^2+(1)^2+(-2)^2 | & (- i + k ) (2 i + j -2 k )= | array ccc i & j & k -1 & 0 & 1 2 & 1 & -2 array |= i (0-1)- j (2-2)+ k (-1-0)=- i - k & d = | - i - k 9 |= 2 3 units aligned