Let the line L1:x+3=0 intersect the lines L2:x−y=0 and L3:3x+y=0 at the points A and B , respectively. Let the bisector of the obtuse angle between the lines L2 and L3 intersect the line L1 at the point C . Then BC2:AC2 is equal to :
(A)5:1✓ Correct
(B)1:5
(C)2:3
(D)3:2
Answer: (A)
Solution
The line x=−3 meets y=x at A(−3,−3) and y=−3x at B(−3,9). The bisectors of the angles between x−y=0 and 3x+y=0 are 2x−y=±103x+y. Since a1a2+b1b2=(1)(3)+(−1)(1)=2>0, the obtuse-angle bisector is taken with the + sign, meeting x=−3 at C=(−3,35−6). Then AC2=(35−3)2 and BC2=(35−15)2, so AC2BC2=(35−3)2(35−15)2=5. Hence BC2:AC2=5:1.
JEE Main · 2026 · 04 Apr 2026 · Shift 1 · Single correct option