Q. Write an equation for an ellipse centered at the origin, which has foci at (0,±15) and vertices at (0,±25).
Identify coordinates of foci and vertices: Identify the coordinates of the foci and vertices.Foci: (0,±15)Vertices: (0,±25)Since both foci and vertices lie on the y-axis, the ellipse is vertical.
Determine values of a and c: Determine the values of a and c. The distance from the center to a vertex is 'a', and the distance from the center to a focus is 'c'. a=25 (since the vertices are at (0,±25)) c=15 (since the foci are at (0,±15))
Calculate value of b: Calculate the value of b using the relationship c2=a2−b2.c2=a2−b2152=252−b2225=625−b2b2=625−225b2=400b=400b=20
Write equation in standard form: Write the equation of the ellipse in standard form.Since the ellipse is vertical, the standard form of the equation is b2x2+a2y2=1.Substitute the values of a and b:202x2+252y2=1400x2+625y2=1
Simplify equation if necessary: Simplify the equation if necessary.The equation is already in its simplest form, so no further simplification is needed.Final equation: 400x2+625y2=1
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