Сложение рациональных дробей!(Желательно 6 и 8) 2 и 4 не надо!

6) 1/(2m-4) + m/(4-m^2) = (4-m^2 +2m^2-4m)/(2m-4)(4-m^2) == (m^2 - 4m +4)/(2m-4)(4-m^2) = (m-2)^2/2(m-2)(4-m^2) = (m-2)/2(4-m^2)  == -(2-m)/2(2-m)2+m) = -1/2(2+m)8) b/(3b-1) + (3b^2-1)/(1-9b^2) = -b/(1-3b) + (3b^2 - 1)/(1-3b)(1+3b) = = (-b-3b^2+3b^2+1)/(1-3b)(1+3b) = (1-b)/(1-3b)(1+3b) = (1-b)/(1-9b^2)