Q.

Let the line L intersect the lines x – 2 = – y = z – 1, 2(x + 1) = 2(y –1) = z + 1 and be parallel to the line x23=y11=z22. Then which of the following points lis on L          [2024]

1 (13,1,1)  
2 (13,1,1)  
3 (13,1,1)  
4 (13,1,1)  

Ans.

(2)

L1 : x21=y1=z11=λ

L2 : x+1(1/2)=y1(1/2)=z+11=μ

Any point on L1 and L2 will be of the form (λ+2,λ,λ+1) and (μ21,μ2+1,μ1) respectively.

Now direction ratios of line L are given by

< λμ2+3, λμ21, λμ+2>

Also L is parallel to line x23=y11=z22

 λμ2+33=λμ211=λμ+22

 λμ2+3=3λ3μ23        ... (i)    2(λμ2+3)=3(λμ+2)     ... (ii)}   λ=43,  μ=23

  Points will be (23,43,13) and (43,23,53)

  L is given by x233=y431=z+132

Point (13,1,1) will satisfy this line L.