(1/5m-1/2n)(1/25㎡+1/10mn+1/4n²)
问题描述:
(1/5m-1/2n)(1/25㎡+1/10mn+1/4n²)
答
(1/5m-1/2n)(1/25㎡+1/10mn+1/4n²)
=(1/5m)³-(1/2n)³
=1/125m³-1/8n³