dadya
幼苗
共回答了15个问题采纳率:100% 举报
(m+1)(m+11) = m^2 + m +11m +11 (注:m^2是指m的平方,下同)
(m+1)(m-11) = m^2 + m -11m -11
(m-1)(m+11) = m^2 - m +11m - 11
(m-1)(m-11) = m^2 - m -11m +11
规律是:每个结果中二次项的系数都是1,一次项的系数等于各多项式中常数项之和,常数项等于各多项式中常数项之积.
所以 ,(x - k)(x - m) = x^2 - (k+m)x + km
1年前
6