m(m+1)(m+2)(m+3)+1
=(m²+3m)(m²+3m+2)+1
=(m²+3m)²+2(m²+3m)+1
=(m²+3m+1)²
:m(m+1)(m+2)(m+3)+1是一个完全平方式步骤二是什么意思呢？m(m+1)(m+2)(m+3)+1
=[m(m+3)][(m+2)(m+1)]+1
=(m²+3m)(m²+3m+2)+1