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Solve the differential equation ydydx+x = 0

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Question

Solve the differential equation

`y (dy)/(dx) + x` = 0

Sum
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Solution

Given differential equation is `y (dy)/(dx) + x` = 0

⇒ `y (dy)/(dx)` = – x

⇒ y dy = – x dx

On integrating both sides, we get

`int y  dy = int - x  dx`

⇒ `y^2/2 = (-x^2)/2 + C`

⇒ y2 + x2 = 2C

⇒ x2 + y2 = C

Where C = 2C is the required solution of differential equation.

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2021-2022 (March) Set 1

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