題組內容
四、X的動差母函數為\(M_X(t) = \left(\frac{1}{4}\right)(e^t + e^{2t} + e^{3t} + e^{4t})\),Y的動差母函數為\( M_Y(t) = \left(\frac{1}{a}\right) (e^t + \)\(e^{2t} + e^{3t}\)),X和Y為獨立隨機變數。設W=X+Y。試求:
(1)W的動差母函數?(5分)
四、X的動差母函數為\(M_X(t) = \left(\frac{1}{4}\right)(e^t + e^{2t} + e^{3t} + e^{4t})\),Y的動差母函數為\( M_Y(t) = \left(\frac{1}{a}\right) (e^t + \)\(e^{2t} + e^{3t}\)),X和Y為獨立隨機變數。設W=X+Y。試求:
(1)W的動差母函數?(5分)