Ex 11.3, 11 - Chapter 11 Class 11 Conic Sections

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Ex 11.3, 11 Find the equation for the ellipse that satisfies the given conditions: Vertices (0, 13), foci (0, 5) Given Vertices (0, 13) Hence The vertices are of the form (0, a) Hence the major axis is along y-axis & equation of ellipse is of the form 2 2 + 2 2 = 1 From (1) & (2) a = 13 Also given coordinate of foci = (0, 5) We know that foci are = (0, c) So c = 5 We know that c2 = a2 b2 (5) 2 = (13) 2 b2 b2 = (13) 2 (5) 2 b2 = 169 25 b2 = 144 Equation of ellipse is 2 2 + 2 2 = 1 Putting value 2 144 + 2 169 = 1