(((m² - 3m + 9)/(9m² - 1)) · ((3m² + m)/(m³ + 27)) - ((m + 3)/(3m² - m))) ÷ (7/(m² + 3m))- - ((15m + 6)/(7 - 21m)) =
1) (m² - 3m + 9)/(9m² - 1)) · ((3m² + m)/(m³ + 27)) = ((m² - 3m + 9)/(3m - 1)(3m + 1)) · ·(m(3m + 1)/(m + 3)(m² - 3m + 9)) = (m² - 3m + 9)m(3m + 1)/(3m - 1)(3m + 1)(m + 3)(m² - 3m + 9) = m/(3m - 1)(m + 3)
2) (m/(3m - 1)(m + 3)) - ((m + 3)/(3m² - m)) = (m/(3m - 1)(m + 3)) - ((m + 3)/m(3m - 1)) =
= (m · m/m(3m - 1)(m + 3)) - ((m + 3)(m + 3)/m(3m - 1)(m + 3)) = m² - (m + 3)(m + 3) /m(3m - 1)(m + 3) = (m² - (m² +2 · 3 · m + 3 · 3))/m(3m - 1)(m + 3) = (m² - m² - 6m -
- 9)/m(3m - 1)(m + 3) = ((-6m) - 9)/m(3m - 1)(m + 3)
3) ((-6m) - 9)/m(3m - 1)(m + 3)) ÷ (7/(m² - 3m)) = ((-6m) - 9)/m(3m - 1)(m + 3) ÷ (7/m (m - 3)) = ((-6m) - 9)/m(3m - 1)(m + 3) · (m(m - 3)/7) = (-3)(2m + 3)m(m - 3))/m(3m - 1)(m + 3) · 7 = (-3)(2m + 3)(m - 3)/(3m - 1)(m + 3) · 7
4) ((-3)(2m + 3)(m - 3)/(3m - 1)(m + 3) · 7) - ((15m + 6)/(7 - 21m)) = ((-3)(2m + 3)(m - 3)/ /(3m - 1)(m + 3) · 7) - ((15m + 6)/(-7)(3m - 1)) = ((-3)(2m + 3)(m - 3)(-1)/(3m - 1)(m + 3) · 7 · (-1)) - ((15m + 6)(m + 3)/(-7)(3m - 1)(m + 3) = ((-3)(2m + 3)(m - 3)(-1) - (15m + 6)(m + 3))/(-7)(3m - 1)(m + 3) = ((6m + 9)(m - 3) - (15m² + 6m + 45m + 18))/(-7)(3m - 1)(m + 3)
= (6m² + 9m - 18m - 27 - 15m² - 6m - 45m - 18)/(-7)(3m - 1)(m + 3) = (-9m² - 60m - -45)/(-7)(3m - 1)(m + 3) = (-9m² - 60m - 45)/((-21m) + 7)(m + 3) = (-9m² - 60m - 45) /((-21m²) +7 m + 21 - (-63m)) = (-9m² - 60m - 45)/((-21m²) - 56m + 21) = -3(3m² + 20
· m + 1,3)/(-3)(7m² + 18,7m - 7) = (3m² + 20m + 1,3)/(7m² + 18,7m - 7)