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Question
Solve the differential equation xdx + 2ydy = 0
Solution
xdx + 2ydy = 0
Integrating on both sides, we get
`int x "d"x + 2inty "d"y` = 0
∴ `x^2/2 + 2(y^2/2)^2` = c1
∴ x2 + 2y2 = c, where c = 2c1
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