Question
Let and be the slopes of the tangents drawn from the point to the hyperbola . If is the point from which the tangents drawn to have slopes and and they make positive intercepts and on the -axis, then is equal to __________.
Answer: 2
Solution
This problem combines the concept of tangents to a hyperbola, specifically using the slope form, with careful analysis of x-intercepts and coordinate geometry. We will break down the solution into clear, manageable steps.
Key Concept: Tangent Equation of a Hyperbola in Slope Form For a hyperbola of the form (transverse axis along the y-axis), the equation of a tangent with slope is given by: This formula is critical for solving the problem. Note that the sign before the square root depends on the specific tangent and