Tính M M= 100.100-99.999+98.98- 97.97+ …+2.2 – 1.1 11/07/2021 Bởi Gianna Tính M M= 100.100-99.999+98.98- 97.97+ …+2.2 – 1.1
M= 100.100-99.999+98.98- 97.97+ …+2.2 – 1.1 =(100-99)(100+99)+(98-97)(98+97)+…+(2-1)(2+1) =100+99+98+97+…+2+1 =(1+100).100:2 =5050 Bình luận
M= 100.100-99.999+98.98- 97.97+ …+2.2 – 1.1
=(100-99)(100+99)+(98-97)(98+97)+…+(2-1)(2+1)
=100+99+98+97+…+2+1
=(1+100).100:2
=5050