将分式m/m^2-6m+9.-3M/2M^2-18.1/2m+6通分后,其分子之和是多少?

将分式m/m^2-6m+9.-3M/2M^2-18.1/2m+6通分后,其分子之和是多少?
将分式m/m^2-6m+9.-3M/2M^2-18.1/2m+6通分后,其分子之和是多少?

将分式m/m^2-6m+9.-3M/2M^2-18.1/2m+6通分后,其分子之和是多少?
m/m^2-6m+9.-3M/2M^2-18+1/2m+6
=m/（m-3)^2-3m/2(m+3)(m-3)+1/2(m+3)
=9(m+1)/2（m-3)^2(m+3)
分子之和是=9(m+1)