(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)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