Given ` xdy = (x + y + 2)dx `
=> `xdy/dx = (x + y + 2)`
=> `y'=1+y/x+2/x`
=> `y'-y/x = 1+2/x`
=> `y'-y/x =(x+2)/x`
when the first order linear ordinary differential equation has the form of
`y'+p(x)y=q(x)`
then the general solution is ,
`y(x)=((int e^(int p(x) dx) *q(x)) dx +c)/e^(int p(x) dx)`
so,
`y'-y/x =(x+2)/x--------(1)`
`y'+p(x)y=q(x)---------(2)`
on comparing both we get,
`p(x) = -1/x and q(x)=(x+2)/x`
so on solving with the above...
Given ` xdy = (x + y + 2)dx `
=> `xdy/dx = (x + y + 2)`
=> `y'=1+y/x+2/x`
=> `y'-y/x = 1+2/x`
=> `y'-y/x =(x+2)/x`
when the first order linear ordinary differential equation has the form of
`y'+p(x)y=q(x)`
then the general solution is ,
`y(x)=((int e^(int p(x) dx) *q(x)) dx +c)/e^(int p(x) dx)`
so,
`y'-y/x =(x+2)/x--------(1)`
`y'+p(x)y=q(x)---------(2)`
on comparing both we get,
`p(x) = -1/x and q(x)=(x+2)/x`
so on solving with the above general solution we get:
y(x)=`((int e^(int p(x) dx) *q(x)) dx +c)/e^(int p(x) dx)`
=`((int e^(int (-1/x) dx) *((x+2)/x)) dx +c)/e^(int (-1/x) dx)`
first we shall solve
`e^(int (-1/x) dx)=e^(ln(1/x)) = (1/x)`
so
proceeding further, we get
y(x) =`((int e^(int (-1/x) dx) *((x+2)/x)) dx +c)/e^(int (-1/x) dx)`
=`((int (1/x) *((x+2)/x)) dx +c)/(1/x)`
=`(int (1/x) *((1+(2)/x)) dx +c)/(1/x)`
=` x(ln(x)-2/x +c)`
so now let us find the particular solution of differential equation at y(1)=10
`y(1) = 1(ln(1)-2/1 +c)`
=> `10 = 0-2+c`
`c=12`
`y(x) =x(ln(x)-2/x +12)` is the solution
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