數學題已知代數式(2x+m)(3x+2)-nx(x+3)+5的值與x的值無關,求mn的值

數學題已知代數式(2x+m)(3x+2)-nx(x+3)+5的值與x的值無關,求mn的值

6x2 + 4x +2m + 3mx - nx2 - 3nx +5
=(6-n)x2 +(4+3m -3n)x +5
n = 6 m = 14/3