Question

A={ x€N|2 la puterea x mai mic sau egal 8}, B={ x€ N|7 la puterea x+2<9} va rog

Answer 1

A= {0.1;2;3}
pt ca 2^0=1≤8
2^1=2≤8
2²=4≤8
2³=8≤8

pt B  rezolvam 7^x+2<9
deci 7^x<9-2
 7^x<7
  verificam 7^0=1<7
7^1=7care nu <7
deci B={0}