(1)X∼exp(1)X\sim \exp(1)X∼exp(1),Y∼exp(1)Y\sim \exp(1)Y∼exp(1),
- PDF:fX(x)=e−x,x>0f_{X}(x)=e^{-x},x>0fX(x)=e−x,x>0;fY(y)=e−y,y>0f_{Y}(y)=e^{-y},y>0fY(y)=e−y,y>0
- CDF:FX(x)=1−e−xF_{X}(x)=1-e^{-x}FX(x)=1−e−x
- 特征函数:ϕX(w)=11−jw\phi_{X}(w)=\frac{1}{1-jw}ϕX(w)=1−jw1
(2)Y=aX∼exp(a)Y=aX\sim \exp(a)Y=aX∼exp(a)
- PDF:fY(y)=1ae−ya,y>0f_{Y}(y)=\frac{1}{a}e^{-\frac{y}{a}},y>0fY(y)=a1e−ay,y>0
- CDF:FY(y)=1−e−yaF_{Y}(y)=1-e^{-\frac{y}{a}}FY