若2m+n=3,则4m^2+8mn+n^2-6的值为

2025-05-16 18:34:26
推荐回答(2个)
回答1:

(2m+n)^2=4m^2+4mn+n^2=9
4m^2+8mn+n^2-6=(4m^2+4mn+n^2)+4mn-6=9+4mn-6=4mn+3

回答2:

3