Răspuns: Ai mai jos demostratia
Explicație pas cu pas:
[tex]\bf A = 2\cdot 5^{x}+3\cdot 5^{x+1}+4\cdot 5^{x+2}[/tex]
[tex]\bf A = \green{\underline{5^{x}}}\cdot \Big(2\cdot 5^{x-x}+3\cdot5^{x+1-x}+4\cdot 5^{x+2-x}\Big)[/tex]
[tex]\bf A = 5^{x}\cdot \Big(2\cdot 5^{0}+3\cdot5^{1}+4\cdot 5^{2}\Big)[/tex]
[tex]\bf A = 5^{x}\cdot \Big(2\cdot 1+3\cdot5+4\cdot 25\Big)[/tex]
[tex]\bf A = 5^{x}\cdot \Big(2+15+100\Big)[/tex]
[tex]\bf A = 5^{x}\cdot 117[/tex]
[tex]\bf A = 5^{x}\cdot 3\cdot 39 ~~\vdots~~39 \implies \red{\underline{A ~~\vdots~~39}}[/tex]
==pav38==
