Объяснение:

[tex]2) \frac{4 {m}^{2} }{ - 8 {m}^{3} } = \frac{4 {m}^{2} }{ 4 {m}^{2} \times ( - 2m) } = \frac{1}{ - 2m} [/tex]

[tex]4) \frac{ - 12 {m}^{4} }{18 {m}^{2} } = \frac{ - 2 {m}^{2} \times 6 {m}^{2} }{3 \times 6 {m}^{2} } = \frac{ - 2 {m}^{2} }{3} [/tex]

[tex]6) \frac{ - 63a {b}^{5} }{81a {b}^{4} } = \frac{ - 7b \times 9 a{b}^{4} }{9 \times 9a {b}^{4} } = \frac{ - 7b}{9} [/tex]

[tex]8) \frac{111 {a}^{6} {b}^{6} }{37 {a}^{4} {b}^{4} } = \frac{3 {a}^{2} {b}^{2} - 37{a}^{4} {b}^{4} }{37 {a}^{4} {b}^{4} } = 3{a}^{2} {b}^{2} [/tex]