展越和温柠的小说全文:证明:X(X+1)(X+2)(X+3)+1是完全平方

来源:百度文库 编辑:高校问答 时间:2024/05/06 06:07:39

X(X+1)(X+2)(X+3)+1=X^4+6X^3+11X^2+6X+1=(X^2+3X+1)^2

X(X+1)(X+2)(X+3)+1
=(X+1)(X+2)(X+3)X+1
=(X^2+3X)(X^2+3X+2)+1
=(X^2+3X)^2+2*(X^2+3X)+1
=(X^2+3X+1)^2

X(X+1)(X+2)(X+3)+1
=(X+1)(X+2)(X+3)X+1
=(X^2+3X)(X^2+3X+2)+1
=(X^2+3X)^2+2*(X^2+3X)+1
=(X^2+3X+1)^2

X(X+1)(X+2)(X+3)+1=(x+0)*(X+1)(X+2)(X+3)+1==(X^2+3X+1)^2

撑开来就可以作了~

X(X+1)(X+2)(X+3)+1
=(X+1)(X+2)(X+3)X+1
=(X^2+3X)(X^2+3X+2)+1
=(X^2+3X)^2+2*(X^2+3X)+1
=(X^2+3X+1)^2