(2n+1)²- (2n-1)²=8n 化简快点啊!
来源:学生作业帮助网 编辑:作业帮 时间:2024/11/15 04:03:30
x)06TS64U ta<[<=ӞkxOv)$I~
YECTjA|F<;6`AmFZ&y8v%EhFr!jb`0S"gwx Q;w
(2n+1)²- (2n-1)²=8n 化简快点啊!
(2n+1)²- (2n-1)²=8n 化简
快点啊!
(2n+1)²- (2n-1)²=8n 化简快点啊!
[(2n+1)- (2n-1)]*[(2n+1)+(2n-1)]=8n
[(2n+1)- (2n-1)]*[(2n+1)+(2n-1)]=2*4n=8n
(2n+1)²- (2n-1)²
=[(2n+1)+(2n-1)][(2n+1)-(2n-1)]
=(2n+1+2n-1)(2n+1-2n+1)
=4n×2
=8n