Salut,
Avem că:
[tex]13^{2021}=13\cdot 13^{2020}=13\cdot 13^{1010\cdot 2}=13\cdot(13^{1010})^2=(4+9)\cdot(13^{1010})^2=\\\\=(2^2+3^2)\cdot(13^{1010})^2=2^2\cdot(13^{1010})^2+3^2\cdot(13^{1010})^2=(2\cdot13^{1010})^2+(3\cdot13^{1010})^2.[/tex]
Ai înțeles rezolvarea ?
Green eyes.
