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Question
Solve the following differential equation.
`dy/dx + y` = 3
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Solution
`dy/dx + y` = 3
The given equation is of the form
`dy/dx + py = Q`
where, P = 1 and Q = 3
∴ I.F. = `e int^(pdx) = e int^ (1dx) = e^x`
∴ Solution of the given equation is
`y(I.F.) = int Q(I.F.) dx + c`
∴ `ye^x = int 3e^x dx + c`
∴ yex = 3ex + c
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