Solving Inhomogeneous equation

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Homework Statement


Solve the inhomogeneous equation y'' + 4y = 4 with y(0)=0 and y'(0)=0.


The Attempt at a Solution



let Y(t) = A, A being some constant
Y'(t) = 0
Y''(t) = 0

Y''(t)+4Y(t)=4
=> 4Y(t)=4
=> 4A=4
=> A=1
=> y(t)=1
But y(0)=0, so that cannot be correct.

Any tips?
 
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It looks like y is not a constant function; but a variable function that satisfies y'' + 4y = 4 with y(0)=0 and y'(0)=0.
 
EnumaElish said:
It looks like y is not a constant function; but a variable function that satisfies y'' + 4y = 4 with y(0)=0 and y'(0)=0.

Yeah, I saw that, but how could I go about solving it if the right hand side is constant?
 
The function y(t)=1 is a particular solution. You have to add this to the general solution of the homogeneous equation. Can you find it?
 
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