Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
COMEDK2024MathematicsThree Dimensional GeometryActual

If the line 1-x -3 =y= z+2 2 is perpendicular to the line 3 x-1 2 b =3-y= z-1 a , then find the value of 3 a+3 b

Options

  1. A3 2
  2. B4
  3. C1 2
  4. D3

Correct answer

A. 3 2

Step-by-step solution

The first line is given by x-1 3 = y 1 = z+2 2 . The direction vector of this line is v₁ = 3 i + 1 j + 2 k . The second line is given by 3x-1 2b = y-3 -1 = z-1 a . Rewriting this in standard form x - 1/3 2b/3 = y-3 -1 = z-1 a . The direction vector of this line is v₂ = 2b 3 i - 1 j + a k . Since the lines are perpendicular, the dot product of their direction vectors must be zero: v₁ v₂ = 0 . (3) ( 2b 3 ) + (1)(-1) + (2)(a) = 0 . 2b - 1 + 2a = 0 . 2a + 2b = 1 . We need to find the value of 3a + 3b . 3(a + b) = 3 1 2

Practice Three Dimensional Geometry on Quantrex Academy →

More from Three Dimensional Geometry

The circum radius of the triangle formed by the points (2,-1,1),(1,-3,-5) and (3,-4,-4) is 2025Let A (2,3,5), B (-1,3,2), C ( , 5, ) be the vertices of ABC . If the median through the vertex A is equally inclined to the coordinate axes, then 2025Equation of the plane passing through the origin and perpendicular to the planes x+2 y-z=1 and 3 x-4 y+z=5 is 2025If the line joining the points i +2 j and j -2 k intersects the plane passing through the points 2 i - j , 2 j +3 k and k -2 i at r , then r ( i + j + k )= 2025The vector equation of a plane passing through the line of intersection of the planes r ( i -2 k )=3, r (2 j + k )=5 and the point i +2 j +3 k is 2025The points A (-1,2,3), B (2,-3,1), C (3,1,-2) 2025The direction cosines of the line making angles 4 , 3 and (0 < < 2 ) respectively with X , Y and Z axes are 2025If the equation of the plane passing through the point (3,2,5) and perpendicular to the planes 2 x-3 y+5 z=7 and 5 x+2 y-3 z=11 is x+b y+c z+d=0 , then 2 b+3 c+d= 2025 Full Three Dimensional Geometry list All COMEDK PYQs