Răspuns :
Răspuns:
√a=12^n·6^2 √a∈N
Explicație pas cu pas:
3^(2n+3)·4^(2n+3)-2^(2n+1)·6^(2n+3)= 3^(2n+3)·(2^2)^(2n+3)-2^(2n+1)·6^(2n+3)=
3^(2n+3)·(2)^[2·(2n+3)]-2^(2n+1)·6^(2n+3)=
3^(2n+3)·2^(2n+3)·2^(2n+3)-2^(2n+1)·6^(2n+3)=
6^(2n+3)·[2^(2n+3)-2^(2n+1)]=6^(2n+3)·[2^2n·2^3-2^2n·2]= 6^(2n+3)·2^2n(2^3-2)]= 6^(2n+3)·2^2n·6=6^2n·6^3·2^2n·6= 6^2n·2^2n·6^4 a=6^2n·2^2n·6^4
√a=√(6^2n·2^2n·6^4)=6^n·2^n·6^2=12^n·6^2
√a=12^n·6^2 √a∈N