Let the angles made with the positive x-axis by two straight lines drawn from the point P(2, 3) and meeting the line x + y = 6 at a distance 23 from the point P be 1 and 2. Then the value of ( 1 + 2) is:
- 2
- 3
- 12
- 6
Answer
(1) 2
Solution
A point at distance r from P(2, 3) along a line inclined at θ: (2 + r , 3 + r )
It lies on x + y = 6: 5 + r( + ) = 6
With r = 23: + = 32
⇒ 2 ( + 4 ) = 32 ⇒ ( + 4 ) = 32
⇒ + 4 = 3 or 2 3 ⇒ 1 = 12, 2 = 5 12
∴ 1 + 2 = 2
Answer: (1)