The lines L1:y−x=0 and L2:2x+y=0 intersect the line L3:y+2=0 at P and Q respectively. The bisector of the acute angle between L1 and L2 intersect L3 at R. Statement -1 : The ratio PR:RQ equals 22:5. Statement-2: In any triangle, bisector of an angle divides the triangle into two similar triangles.
(A)Statement -1 is true, Statement -2 is true; Statement -2 is not a correct explanation for Statement - 1
(B)Statement -1 is true, Statement- 2 is false.✓ Correct
(C)Statement -1 is false, Statement- 2 is true.
(D)Statement -1 is true, Statement -2 is true; Statement -2 is a correct explanation for Statement -1
Answer: (B)
Solution
The line L1:y=x meets L3:y=−2 at P(−2,−2), and L2:y=−2x meets it at Q(1,−2). The bisector of the acute angle between L1 and L2 passes through the origin and meets L3 at R; working out that bisector and its intersection gives the division ratio PR:RQ=22:5, so the first statement is true. The second statement, that an angle bisector splits a triangle into two similar triangles, is false in general, so here the first statement is true and the second is false.
JEE Main · 2011 · 10 Apr 2011 · Offline · Single correct option