а) 7/x + 1/4x = (28 + x) / 4x
б) 1/x-2 - 1/x+2 = (1 (x+2) - 1 (x-2)) / (x^2-2^2) = 4 / (x^2 - 4)
в) 3a * 5b/3a^2 = 5b / a
г) (3xy^2/4a) : (13y/24a^2b) = (3xy^2 24a^2b) / (4a 13y) = 72a^2by^2 / 52ay = (6/13)ab
а) 7/x + 1/4x = (28 + x) / 4x
б) 1/x-2 - 1/x+2 = (1 (x+2) - 1 (x-2)) / (x^2-2^2) = 4 / (x^2 - 4)
в) 3a * 5b/3a^2 = 5b / a
г) (3xy^2/4a) : (13y/24a^2b) = (3xy^2 24a^2b) / (4a 13y) = 72a^2by^2 / 52ay = (6/13)ab