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प्रश्न
Find the equation of the ellipse in standard form if the length of major axis 10 and the distance between foci is 8
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उत्तर
Let the equation of the ellipse be
`x^2/"a"^2 + y^2/"b"^2` = 1 ...(1)
Then length of major axis = 2a = 10
∴ a = 5
Also, distance between foci = 2ae = 8
∴ 2 × 5 × e = 8
∴ e = `4/5`
∴ b2 = `"a"^2(1 - "e"^2)`
= `5^2 [1 - (4/5)^2]`
= `25(1 - 16/25)`
= 9
∴ from (1), the equation of the required ellipse is `x^2/25 + y^2/9` = 1.
संबंधित प्रश्न
Answer the following:
Find the
- lengths of the principal axes
- co-ordinates of the foci
- equations of directrices
- length of the latus rectum
- distance between foci
- distance between directrices of the ellipse:
`x^2/25 + y^2/9` = 1
Find the
- lengths of the principal axes.
- co-ordinates of the focii
- equations of directrics
- length of the latus rectum
- distance between focii
- distance between directrices of the ellipse:
3x2 + 4y2 = 12
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