Если m и n корни квадратного уравнения 2x²-3x-6=0. то значение выражения

(6+5m) / m + (6-7n) / n =

2x²-3x-6=0

D=9+48=57

x = (3-√57) / 4=m U x = (3+√57) / 4=n

(6+5m) / m = (6+5 (3-√57) / 4) : (3-√57) / 4 = (24+15-5√57) / 4*4 / (3-√57) =

= (39-5√57) / (3-√57) = (39-5√57) (3+√57) / (3-√57) (3+√57) =

= (117+39√57-15√57-285) / (9-57) = (24√57-168) / (-48) = 24 (√57-7) / (-48) = (7-√57) / 2

(6-7n) / n = (6-7 (3+√57) / 4) : (3+√57) / 4 = (24-21-7√57) / 4*4 / (3+√57) =

= (3-7√57) / (3+√57) = (3-7√57) (3-√57) / (3+√57) (3-√57) =

= (9-3√57-21√57+399) / (-48) = (390-24√57) / (-48) = 6 (65-4√57) / (-48) = (4√57-65) / 8

(6+5m) / m + (6-7n) / n = (7-√57) / 2 + (4√57-65) / 8 = (28-4√57+4√57-65) / 8=-37/8=-4,625