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问题: 已知数列{Xn},{Yn},满足,lim(2Xn+Yn)=1,lim(Xn-2Yn)=1,

已知数列{Xn},{Yn},满足,lim(2Xn+Yn)=1,lim(Xn-2Yn)=1,求lim(Xn*Yn)

解答:

lim(2Xn+Yn) =2*limXn +limYn =1
lim(Xn-2Yn) =limXn -2*limYn =1
==> limXn =3/5, limYn =-1/5
lim(Xn*Yn) =limXn*limYn =-3/25