Q.

If the image of the point (4, 4, 3) in the line x12=y21=z13 is (α,β,γ), then α+β+γ is equal to          [2025]

1 9  
2 7  
3 12  
4 8  

Ans.

(1)

Let x12=y21=z13=λ

 M(2λ+1,λ+2,3λ+1)

PM=(2λ3)i^+(λ2)j^+(3λ2)k^

Since, PM is perpendicular to the given line

  2(2λ3)+1(λ2)+3(3λ2)=0

 λ=1

   The coordinates of point M is (3, 3, 4).

Let Q be the image of the point P. Then, M be the mid-point of PQ.

  (4+α2,4+β2,3+γ2)(3,3,4)

 α=2,β=2,γ=5        α+β+γ=9