Here f:Z36 to Z4 x Z9 is group isomorphism given by f(n+36Z)= (n+4Z,

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here f:Z36 to Z4 x Z9 is group isomorphism given by f(n+36Z)= (n+4Z, n+9Z) then what is the inverse of f ?
 
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goody said:
here f:Z36 to Z4 x Z9 is group isomorphism given by f(n+36Z)= (n+4Z, n+9Z) then what is the inverse of f ?

Maybe write out a few (n, f(n)) pairs, and see if you can find a pattern? Does "Chinese remainder theorem" ring a bell?
 
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