A= 5/9*7/13+5/9*6/13
B=(1/99+12/999+123/9999)*(1/2-1/3-1/6)
tính
Viết các số sau dưới dạng số thập phân
1/9 , 7/9 ,5/90 , 7/900 , 13/99 , 21/99 , 32/99 ,53/99 ,12/990 , 46/9900, 123/999 , 456/999 , 14234/9999 , 13/9999 , 7/99900, 230/99900 , 7/999 , 33/9999 , 17/999000 , 230/999900
\(\frac{1}{9}\),\(\frac{7}{9}\),\(\frac{5}{90}\),\(\frac{7}{900}\),\(\frac{13}{99}\),\(\frac{21}{99}\),\(\frac{32}{99}\),\(\frac{53}{99}\),\(\frac{12}{990}\),\(\frac{46}{9900}\),\(\frac{123}{999}\),\(\frac{456}{999}\),\(\frac{14234}{9999}\),\(\frac{13}{9999}\),\(\frac{7}{99900}\),\(\frac{230}{99900}\),\(\frac{7}{999}\),\(\frac{33}{9999}\),\(\frac{17}{999000}\),\(\frac{230}{999900}\)
a) 8/5 x 2/5 x 3/8 x 10 x 19/192
b) ( 1/99 + 12/999 - 123/9999) x (1/2 - 1/3 - 1/6)
13-(1/99+12/999-123/9999).(1/2-1/3-1/6)
làm chi tiết
(1/99+12/999+123/9999).(1/2-1/3-1/6)
Chỉ cần tính 1/2-1/3-1/6=6/12-4/12-2/+2=0/12=0
Suy ra (1/99+12/999+123/9999).(1/2-1/3-1/6)=(1/99+12/999+123/9999).0=0
Vậy kết quả là 0.
mk nha
(1/99+12/999-123/9999).(1/2-1/3-1/6)
(1/99+12/999-123/9999).(1/2-1/3-1/6)
=(9/407-123/9999).0
=0
(1/99+12/999-123/9999).(1/2-1/3-1/6)
5 6545454ffffffffffg6j544gfs46jh5d641bmc3
Q=(1/99+12/999-123/9999).(1/2-1/3-1/6)
\(Q=\left(\frac{1}{99}+\frac{12}{999}+\frac{123}{9999}\right)\left(\frac{1}{2}-\frac{1}{3}-\frac{1}{6}\right)\)
\(Q=\left(\frac{1}{99}+\frac{12}{999}+\frac{123}{9999}\right)0=0\)
( 1/99 + 12/999 - 123/9999) x (1/2 - 1/3 - 1/6)
Tính nhanh :
Q = \(\left(\dfrac{1}{99}+\dfrac{12}{999}+\dfrac{123}{9999}\right).\left(\dfrac{1}{2}-\dfrac{1}{3}-\dfrac{1}{6}\right)\)
Ta có \(\dfrac{1}{2}-\dfrac{1}{3}-\dfrac{1}{6}=\dfrac{1}{6}-\dfrac{1}{6}=0\) nên Q = 0.
\(Q=\left(\dfrac{1}{99}+\dfrac{12}{999}+\dfrac{123}{9999}\right).\left(\dfrac{1}{2}-\dfrac{1}{3}-\dfrac{1}{6}\right)\)
\(Q=\left(\dfrac{1}{99}+\dfrac{12}{999}+\dfrac{123}{9999}\right).0\)
\(Q=0\)