QuestionLet X1X_1 and X2X_2 be i.i.d., where XX has PMF P(X=0)=0.2P(X=0)=0.2, P(X=1)=0.4P(X=1)=0.4, P(X=2)=0.4P(X=2)=0.4. Define Y=X1+X2Y=X_1+X_2. Find the MGF of YY.
