The plane which bisects the line joining the points (4, −2,3) and (2,4, -1) at right angles also passes through the point:
The plane which bisects the line joining the points (4, −2,3) and (2,4, -1) at right angles also passes through the point:
Option 1 -
(0,−1,1)
Option 2 -
(4,0,1)
Option 3 -
(4,0,−1)
Option 4 -
(0,1,−1)
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1 Answer
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Correct Option - 3
Detailed Solution:Mid point P = (3,1,1)
Normal of plane is along the line AB.
D.R.'s of normal = 4-2, -2-4, 3-1 (-1) = 2, -6, 4
= 1, -3, 2
Plane -> 1 (x-3) - 3 (y-1) + 2 (z-1) = 0
=> x - 3y + 2z - 2 = 0
Similar Questions for you
....(1)
Let
Let
Put l1 and l2 in (1)
α = 3
Given , ,
Dot product with on both sides
... (1)
Dot product with on both sides
... (2)
(a – 1) × 2 + (b – 2) × 5 + (g – 3) × 1 = 0
2a + 5b + g – 15 = 0
Also, P lie on line
a + 1 = 2λ
b – 2 = 5λ
g – 4 = λ
2 (2λ – 1) + 5 (5λ + 2) + λ + 4 – 15 = 0
4λ + 25λ + λ – 2 + 10 + 4 – 15 = 0
30λ – 3 = 0
a + b + g = (2λ – 1) + (5λ + 2) + (λ + 4)

Take
x = 2λ + 1, y = 3λ + 2, z = 4λ + 3
= (α − 2)
Now,
(α − 2) ⋅ 2 + (β − 3) ⋅3 + (γ − 4) ⋅ 4 = 0
2α − 4 + 3β − 9 + 4γ −16 = 0
⇒ 2α + 3β + 4γ = 29
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