High school mathematics sequence dislocation want to reduce

High school mathematics sequence dislocation want to reduce

Dislocation subtraction method is a common summation method of sequence, which is applied to the form of multiplication of equal ratio sequence and equal difference sequence. For example, an = bncn, where BN is equal difference sequence and cn is equal ratio sequence; SN is listed separately, and then all formulas are multiplied by the common ratio of equal ratio sequence, that is, KSN at the same time; then the two formulas are subtracted by one bit