JEE Main 2026 Mathematics question
Let a line L be perpendicular to both the lines and . If θ is the acute angle between the lines L and , then tanθ is equal to:
Answer: (B)
Solution
L has direction (3,5,7)×(1,4,7)=(7,−14,7)∥(1,−2,1). L₃ has direction (2,1,2). cosθ=|2−2+2|/(√6·3)=2/(3√6), so tan²θ=25/2 and tanθ=(5/2)√2.