Ответ:

[tex]\frac{7}{8}[/tex]

Объяснение:

[tex]\frac{7a}{a^2-m^2}+\frac{7}{m-a}=\frac{7a}{(a-m)(a+m)}-\frac{7}{a-m}=\frac{7a}{(a-m)(a+m)}-\frac{7(a+m)}{(a-m)(a+m)}=\\\\\frac{7a-7(a+m)}{(a-m)(a+m)}=\frac{7a-7a-7m}{(a-m)(a+m)}=\frac{-7m}{(a-m)(a+m)}\\\\\frac{-7\cdot(-1)}{(-3+1)\cdot(-3-1)}=\frac{7}{-2\cdot(-4)}=\frac{7}{8}[/tex]