Q. Write an equation for an ellipse centered at the origin, which has foci at (0,±15) and co-vertices at (±21,0).
Given Foci and Co-vertices: We are given the foci at (0,±15) and co-vertices at (±21,0). Since the foci are on the y-axis, this indicates that the ellipse is oriented vertically.
Calculating c: The distance between the center and a focus is the value of c in the ellipse equation. We can calculate c using the coordinates of the foci.c=15
Calculating b: The distance between the center and a co-vertex is the value of b in the ellipse equation. We can calculate b using the coordinates of the co-vertices.b=21
Finding a: We know that for an ellipse centered at the origin, the relationship between a, b, and c is given by c2=a2−b2. We can use this to find the value of a. c2=a2−b2 (15)2=a2−(21)2 15=a2−21 a2=15+21 a2=36 b0 b1
Writing the Equation of the Ellipse: Now that we have the values of a and b, we can write the equation of the ellipse in standard form. Since the ellipse is vertically oriented, a2 will be under the y2 term and b2 will be under the x2 term.The standard form of the ellipse is:(x−h)2/b2+(y−k)2/a2=1Plugging in the values for h, k, a, and b, we get:b1b2
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