NTA Abhyas JEE Main2020MathematicsHyperbolaPractice
The locus of a point P α , β moving under the condition that the line y = α x + β is a tangent to the hyperbola x 2 1 - y 2 b 2 = 1 is a conic, with eccentricity equal to
Options
- A1
- B2
- C1 2
- D2
Correct answer
D. 2
Step-by-step solution
The tangent to the hyperbola x 2 1 - y 2 b 2 = 1 is y = m x ± m 2 - b 2 Given that, y = α x + β is a tangent to the hyperbola. So, m = α and m 2 - b 2 = β 2 ∴ α 2 - b 2 = β 2 The locus is x 2 - y 2 = b 2 , which is a hyperbola having eccentricity = 2