`y' + (2x-1)y = 0 , y(1) = 2` Find the particular solution of the differential equation that satisfies the initial condition
Given ` y'+(2x-1)y=0`
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'+(2x-1)y=0--------(1)`
`y'+p(x)y=q(x)---------(2)`
on comparing both we get,
`p(x) = (2x-1) and q(x)=0`
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 (2x-1) dx) *(0)) dx +c)/e^(int (2x-1) dx)`
first we shall solve
`e^(int (2x-1) dx)=e^(x^2 -x) `
so
proceeding further, we get
y(x) =`((int e^(int (2x-1) dx) *(0)) dx +c)/e^(int (2x-1) dx)`
= `((int e^(x^2 -x) *(0)) dx +c)/(e^(x^2 -x) )`
=`0+c/e^(x^2 -x)` = `e^(x-x^2+c ) `
`y(x) =e^(x-x^2+c) `
to find the particular differential equation we have
y(1)=2
=> `y(1)=e^(1-1^2+c)`
=> `e^c =2`
=> `c = ln(2)`
`y(x) = e^(x-x^2+ln(2))`
`y(x) = e^ln2e^(x-x^2)`
So,
`y(x) = 2e^(x-x^2)`
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