m+3m=1
(m-3)/(3m-6m)÷[m+2-5/(m-2)]
=(m-3)/[3m(m-2)]÷[(m-9)/(m-2)]
=(m-3)/[3m(m-2)]x(m-2)/[(m-3)(m+3)]
=1/[3m(m+3)]
=1/[3(m+3m)]
∵m+3m=1
∴原式=1/3
m+3m=1
(m-3)/(3m-6m)÷[m+2-5/(m-2)]
=(m-3)/[3m(m-2)]÷[(m-9)/(m-2)]
=(m-3)/[3m(m-2)]x(m-2)/[(m-3)(m+3)]
=1/[3m(m+3)]
=1/[3(m+3m)]
∵m+3m=1
∴原式=1/3