NTA Abhyas JEE Main2020MathematicsThree Dimensional GeometryPractice
Lying in the plane x + y + z = 6 is a line L passing through 1,2 , 3 and perpendicular to the line of intersection of planes x + y + z = 6 and 2 x - y + z = 4 , then the equation of L is
Options
- Ax - 1 4 = y - 2 - 7 = z - 3 3
- Bx - 1 2 = y - 2 1 = z - 3 - 3
- Cx - 1 4 = y - 2 - 5 = z - 3 1
- Dx - 1 3 = y - 2 1 = z - 3 - 4
Correct answer
C. x - 1 4 = y - 2 - 5 = z - 3 1
Step-by-step solution
Required line lies in the plane x + y + z = 6 so it is perpendicular to i ^ + j ^ + k ^ and it is also perpendicular to line of intersection of the two given planes. Let, n → 1 = i ^ + j ^ + k ^ , n → 2 = 2 i ^ - j ^ + k ^ & ν → be a vector along the required line So, ν → = n → 1 × n → 1 × n → 2 = 2 i ^ + j ^ + k ^ - 3 2 i ^ - j ^ + k ^ = - 4 i ^ + 5 j ^ - k ^ Hence, equation of the line is x - 1 4 = y - 2 - 5 = z - 3 1