The locus of point of intersection of tangents at the ends of normal c...
The Locus of Point of Intersection of Tangents at the Ends of Normal Chord of Hyperbola
The locus of the point of intersection of tangents at the ends of a normal chord of a hyperbola can be determined by considering the properties of the hyperbola and the concept of the normal chord.
Definition of a Hyperbola:
A hyperbola is a conic section defined as the set of all points in a plane, the difference of whose distances from two fixed points (called foci) is constant.
Equation of a Hyperbola:
The equation of a hyperbola with center (h, k), semi-major axis a, and semi-minor axis b can be written as:
[(x - h)² / a²] - [(y - k)² / b²] = 1 --(1)
Given Hyperbola:
For the given hyperbola with equation x² - y² = a², we can rewrite it in the standard form by dividing the equation by a²:
[(x - 0)² / a²] - [(y - 0)² / a²] = 1
From this equation, we can observe that h = 0, k = 0, and a = a.
Finding the Normal Chord:
A normal chord of a hyperbola is a line segment that passes through the focus and is perpendicular to the tangent at that point.
Equation of Tangent to Hyperbola:
The equation of the tangent to a hyperbola at any point (x₁, y₁) on the hyperbola can be determined by differentiating the equation of the hyperbola and substituting the coordinates of the point:
dy/dx = (2x₁) / (-2y₁) --(2)
The equation of the tangent can be written as:
y - y₁ = (dy/dx) * (x - x₁)
Substituting the value of dy/dx from equation (2), we get:
y - y₁ = (x₁ / y₁) * (x - x₁)
Simplifying this equation, we obtain:
y = [(x₁ / y₁) * x] - [(x₁ / y₁) * x₁] + y₁
y = (x₁ / y₁) * x - [(x₁² / y₁) - y₁]
Equation of Normal Chord:
The equation of the normal chord can be determined by finding the slope of the tangent at a particular point and taking the negative reciprocal of it. Let's assume the coordinates of the point on the hyperbola are (x₁, y₁).
The slope of the tangent at (x₁, y₁) is given by dy/dx = (2x₁) / (-2y₁).
The slope of the normal chord can be determined by taking the negative reciprocal of dy/dx:
m₁ = -1 / [dy/dx] = -1 / [(2x₁) / (-2y₁)] = y₁ / x₁
Since the normal chord passes through the focus, its equation can be written as:
y - y₁ = (y₁ / x₁) * (x - x₁) --(3)
Finding the Intersection Point:
To determine the point of intersection of the tangents at the ends of the normal chord, we
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