令y=9m^2+6m+1/(5m^2+6m+2).两边同*(5m^2+6m+2),整理得:(9-5y)m^2+6(1-y)m+1-2y=0.上面方程(以m为未知数)要有解,则:36(1-y)^2-4(9-5y)(1-2y)≥0,解一元二次不等式就可得出y的范围,从而得出最大最小值.(不等式你自己...