√[n*(n+1)*(n+2)*(n+3)+1]化简它
√[n*(n+1)*(n+2)*(n+3)+1]
只要把n*(n+1)*(n+2)*(n+3)+1化成平方数即可
n*(n+1)*(n+2)*(n+3)+1
=n(n+3)(n+1)(n+2)+1
=(n²+3n)(n²+3n+2)+1
=(n²+3n)²+2(n²+3n)+1
=(n²+3n+1)²
原式=n²+3n+1。
=√[(n+1)*(n+2)*n*(n+3)+1] =√[(n^2+3n+2)*(n^2+3n)+1] =√[(n^2+3n)^2+2(n^2+3n)+1] =√(n^2+3n+1)^2 =|n^2+3n+1|
暂时根号不考虑,电脑上打麻烦 n(n+1)(n+2)(n+3)+1 =n(n+3)*[(n+1)(n+3-1)]+1 =n(n+3)[n(n+3)+(n+3)-n-1]+1 =n(n+3)[n(n+3)+2]+1 =n(n+3)^2+2*n(n+3)+1 =[n(n+3)+1]^2 现在考虑根号 =n(n+3)+1 别忘记加绝对值,
因n(n+1)(n+2)(n+3)+1=(n^2+3n)(n^2+3n+2)+1=(n^2+3n)^2+2(n^2+3n)+1=(n^2+3n+1)^2,故:根号[n(n+1)(n+2)(n+3)+1]=n^2+3n+1。