dy/dx+2y=sinx,
The answer is:1/5(2sinx+cosx)+ce^-2x
well, you know that the solution to
y' + 2y = 0
is
y = c e^(-2x)
Now just come up with the other part. Besides your class text, take a look at a similar problem here:
https://au.answers.yahoo.com/question/index?qid=20100317130334AAtWVqs