Expanding the expected value

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How to expand:

$E(Y+1)^2$

my working out:

$E(Y^2)+E(1^2) = E(Y^2)+1$ (I'm not sure why this is though..)

Can someone link to or list the rules for expanding the expected value ......

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Since $(Y+1)^{2}=Y^{2}+2Y+1$ we have $$E[(Y+1)^{2}]=E[Y^{2}+2Y+1]$$ where by properties of linear expectation we have $$=E[Y^{2}]+2E[Y]+1$$ also since $Var[Y]=E[Y^{2}]-(E[Y])^{2}$ we can also write this as $$=Var[Y]+(E[Y])^{2}+2E[Y]+1$$