λ∫[0,+∞)e^[x(1-λ)]dx=λ∫[0,+∞)[e^(1-λ)]^xdx=λ[e^(1-λ)]^x/ln[e^(1-λ)]|[0,+∞)=λe^[x(1-λ)]/(1-λ)|[0,+∞)如果λ>1,那么lim(x→+∞)e^[x(1-λ)]=0x=0时,e^0=1λ∫[0,+∞)e^[x(1-λ)]dx=-λ/(1-λ)如果λ<1,那么lim(x→+∞)e^[x(1-λ)]=+∞λ∫[0,+∞)e^[x(1-λ)]dx=+∞
当年上学没认真,现在看到都不会!