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प्रश्न
Choose the correct option from the given alternatives:
The differential equation `"y" "dy"/"dx" + "x" = 0` represents family of
पर्याय
circles
parabolas
ellipses
hyperbolas
उत्तर
circles
Hint:
`"y" "dy"/"dx" + "x" = 0` ∴ `int "y" "dy" + int "x" "dx"` = c
∴ `"y"^2/2 +"x"^2/2 = "c"`
∴ x2 + y2 = 2c which is a circle.
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