Объяснение:

3m+mk-3n-kn=3(m-n)+k(m-n)=(3+k)(m-n)

[tex]a {}^{8} \times ( {a}^{2}) {}^{ - 3} = {a}^{8} \times {a}^{ - 6} = {a}^{2} [/tex]

[tex]\displaystyle 1)3m+mk-3n-kn=m(3+k)-n(3+k)=(3+k)(m-n)\\\\2)a^8(a^2)^-^3=a^8*a^-^6=a^2[/tex]