2m-{n+[4m-3(m+2n)]}-5n,其中m=3分之2,n=-4化简求值

问题描述:

2m-{n+[4m-3(m+2n)]}-5n,其中m=3分之2,n=-4化简求值

2m-{n+[4m-3(m+2n)]}-5n,
=2m-﹛n+[4m-3m-6n]﹜-5n
=2m-﹛n+m-6n﹜-5n
=2m-m+5n-5n
=m
=2/3