请问19.99*19.98-19.97*19.96简便算法怎么算(*代表乘号)?
来源:学生作业帮助网 编辑:作业帮 时间:2024/07/02 15:26:34
![请问19.99*19.98-19.97*19.96简便算法怎么算(*代表乘号)?](/uploads/image/z/99266-50-6.jpg?t=%E8%AF%B7%E9%97%AE19.99%2A19.98-19.97%2A19.96%E7%AE%80%E4%BE%BF%E7%AE%97%E6%B3%95%E6%80%8E%E4%B9%88%E7%AE%97%EF%BC%88%2A%E4%BB%A3%E8%A1%A8%E4%B9%98%E5%8F%B7%EF%BC%89%3F)
请问19.99*19.98-19.97*19.96简便算法怎么算(*代表乘号)?
请问19.99*19.98-19.97*19.96简便算法怎么算(*代表乘号)?
请问19.99*19.98-19.97*19.96简便算法怎么算(*代表乘号)?
19.99*(19.96+0.02)-19.97*19.96
=19.99*19.96+19.99*0.02-19.97*19.96
=19.99*0.02
=0.3998
原式=(20-0.01)*(20-0.02)-(20-0.03)*(20-0.04)=20*20-(0.01+0.02)*20+0.01*0.02-20*20+(0.03+0.04)*20-0.03*0.04=0.04*20-0.001=0.799