Q. Write an equation for an ellipse centered at the origin, which has foci at (±3,0) and co-vertices at (0,±9).
Ellipse Orientation: We have:Foci: (±3,0)Co-vertices: (0,±9)Choose the orientation of the ellipse.Since the foci are on the x-axis, the ellipse is horizontal.
Finding c: We have:Center (h,k):(0,0)Foci: (±3,0)Identify the value of c (distance from center to foci).c=(3−0)2+(0−0)2=3
Finding b: We have:Center (h,k): (0,0)Co-vertices: (0,±9)Identify the value of b (distance from center to co-vertices).b=((0−0)2+(9−0)2)=(81)=9
Finding a: We know the relationship between a, b, and c for an ellipse is c2=a2−b2. We already have c=3 and b=9. Now we need to find a. c2=a2−b2(3)2=a2−92a0a1a2a3a4
Standard Form of the Ellipse: We know:(h,k)=(0,0)a=221b=9What would be the standard form of the ellipse?(221)2(x−0)2+92(y−0)2=1(221)2x2+92y2=14⋅21x2+81y2=184x2+81y2=1
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