In: Advanced Math
Prove that if U, V and W are vector spaces such that U and V are isomorphic and V and W are isomorphic, then U and W are isomorphic.
Defination : Two vector space V1 and V1 are isomorphic if there exist a linear map T : V1V2 which is bijective .
Now given U and V are isomorphic ,then there exist linear map T1 : UV , which is bijective .
Also given V and W are isomorphic ,then there exist linear map T2 : VW ,which is bijective .
Now T1 : UV and T2 : VW T2 T1 is also a linear map and composition two bijective map is bijective .
T2 T1 is a linear bijective map from U and W .
i.e., there exist a linear bijective map from U to W .
Hence U and W are isomorphic .
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