Điền các dấu \(\left( { \in , \notin } \right)\) thích hợp vào ô vuông:
\(\eqalign{ & 5\,..\,Z\,;\,\,\,\,\,\,\,\,\,\,\,\, - 2\,..\,Q;\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\sqrt 2 \,..\,Q \cr & {3 \over 5}\,..\,Q\,;\,\,\,\,\,\,\,\,\, - {3 \over 5}\,\,..\,I \cr} \)
\(\eqalign{ & 2,31(45)\,\,..\,\,I\,;\,\,\,\,\,\,\,\,\,\,\,\, - 3,45(63)\,\,..\,I \cr & 7,62(38)\,..\,R\,;\,\,\,\,\,\,\,\,\,\,\,\,\,0\,..\,I \cr} \)
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\(\eqalign{ & 5 \in Z; - 2 \in Q;\sqrt 2 \notin Q;{3 \over 5} \in Q; - {3 \over 5} \notin I \cr & 2,31(45) \notin I; - 3,45(63) \notin I;7,62(38) \in R;0 \notin I \cr} \)