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Question
Solve the following differential equation, hence find the particular solution when x = 0, y = 1
`y^3-dy/dx=xdy/dx`
Solution:
`y^3=xdy/dx+dy/dx`
∴ y3 = (x + 1) = `square`
∴ (x + 1)dy = y3 dx
Separating the variables, we get
`1/y^3dy=1/(x+1)dx`
Now integrating, we get
∴ `int1/y^3dy=int1/(x+1)dx`
∴ `-1/(2y^2)=square+c` ...(i)
which is required general solution
put x = 0 and y = 1 in (i)
`-1/(2(1)^2)=log|0 + 1| + c`
∴ `square=c`
∴ `-1/(2y^2)=square-1/2`
is the particular solution.
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Solution
`y^3 = xdy/dx + dy/dx`
∴ y3 = (x + 1)·\[\boxed{\frac{dy}{dx}}\]
∴ (x + 1)dy = y3 dx
Separating the variables, we get
`1/y^3dy = 1/(x + 1)dx`
Now integrating, we get
∴ `int1/y^3dy = int1/(x + 1)dx`
∴ `-1/(2y^2)` = \[\boxed{log|x + 1|}\] + c ...(i)
which is required general solution
put x = 0 and y = 1 in (i)
`-1/(2(1)^2) = log|0 + 1| + c`
∴ \[\boxed{\frac{-1}{2}}\] = c
∴ `-1/(2y^2)` = \[\boxed{log|x + 1|}\]`-1/2`
is the particular solution.
