先化简,再求值:(1+1⼀m-2)⼀(m^2-1⼀2m-4)其中m=5

(1+(m-2)分之1)除以(2m-4)分之m^2-1,其中m=5
2025-03-13 16:00:58
推荐回答(1个)
回答1:

(1+1/m-2)/(m^2-1/2m-4)=(1又1/m-2)/(m^2-1/2m-4)=(m-1/m-2)/m^2-1/2m-4)=(m-1/m-2)*(2m-4/m^2-1)=[(m-1)*(2m-4)]/[(m-2)*(m^2-1)]=(2m^2-6m+4)/(
m^3-m-m^2+2)
当m=5时
(2m^2-6m+4)/(m^3-m-m^2+2)
=(2*5^2-6*5+4)/(125-5-25+2)
=24/97.
希望有用!