\(\Leftrightarrow\frac{2a+b+c}{a}-1=\frac{a+2b+c}{b}-1=\frac{a+b+2c}{c}-1\)
\(\Leftrightarrow\frac{\left(2a+b+c\right)-a}{a}=\frac{\left(a+2b+c\right)-b}{b}=\frac{\left(a+b+2c\right)-c}{c}\)
\(\Rightarrow\frac{a+b+c}{a}=\frac{a+b+c}{b}=\frac{a+b+c}{c}\)
\(\Rightarrow a=b=c\) . Thay vào A ta được :
A = (a + a)(a + a)(a + a) = 2a.2a.2a=8a3
Vậy A = 8a3