Solution
Related Formula
For a horizontal hyperbola centered at (h,k):
((x-h)²)/(a²) - ((y-k)²)/(b²) = 1- Foci: (h ± ae, k)
- Eccentricity relation: b² = a²(e² - 1) = a² e² - a²
Core Logic
Foci are S₁ = (4,2) and S₂ = (8,2).
- Center C(h,k) is the midpoint:
- Distance between foci:
Thus, b² = 4 - a².
Step 1: Expanding standard equation
The equation is:
((x-6)²)/(a²) - ((y-2)²)/(4-a²) = 1 (4-a²)(x-6)² - a²(y-2)² = a²(4-a²)Comparing with 3x² - y² - α x + β y + γ = 0, the ratio of coefficients of x² and y² is (3)/(-1) = -3:
(4 - a²)/(-a²) = -3 4 - a² = 3a² 4a² = 4 a² = 1Thus, b² = 4 - 1 = 3.
Step 2: Finding values of coefficients α, β, γ
Substituting a² = 1 back into standard form equation:
3(x-6)² - (y-2)² = 3 3(x² - 12x + 36) - (y² - 4y + 4) = 3 3x² - 36x + 108 - y² + 4y - 4 = 3 3x² - y² - 36x + 4y + 101 = 0Comparing coefficients:
- α = 36
- β = 4
- γ = 101
Pattern Recognition
Symmetric focal coordinates (y=2) indicate the hyperbola is horizontal. Identifying coordinates of the center (6,2) quickly and using coefficient ratio comparison restricts parameters immediately without requiring complex algebraic systems.
Chapter Mix
Class 11 Conic Sections