\(=\dfrac{6}{7}\cdot\dfrac{14}{9}-1=\dfrac{84}{63}-1=\dfrac{4}{3}-1=\dfrac{1}{3}\)
\(=\dfrac{6}{7}\cdot\dfrac{14}{9}-1=\dfrac{84}{63}-1=\dfrac{4}{3}-1=\dfrac{1}{3}\)
thức hiện hiện mỗi phép tính sau bằng hai cách
a)\(3\dfrac{4}{9}+5\dfrac{1}{6}\), b,\(8\dfrac{1}{14}-6\dfrac{3}{7}\) c,\(7-3\dfrac{6}{7}\)
Tính hợp lý giá trị các biểu thức sau
A=49/8/23-(5/7/32+14/8/23)
C=-3/7.5/9+4/9.-3/7+2/3/7
E=0,7.2/2/3.20.0,375.5/28
H=[9/30303/80808+7/303030/484848]+4,03
I=10101.[5/111111+5/222222-4/3.7.11.13.37]
B=71/38/45-[43/8/45-1/17/57]
D=[19/5/8:7/12-13/1/4:7/12].4/5
F=[9,75.21/3/7+39/4.18/4/7].15/78
(x+9)+(x-8)+(x+7)+(x-6)+(x+4)
Tính bằng cách hợp lí :
a , \(\dfrac{1}{15}+\dfrac{9}{10}+\dfrac{14}{15}-\dfrac{11}{9}-\dfrac{20}{10}+\dfrac{1}{157}\)
b , \(\dfrac{1}{5}-\dfrac{-1}{3}+\dfrac{-1}{5}-\dfrac{2}{6}\)
c , \(\dfrac{2}{1\times3}+\dfrac{2}{3\times5}+...+\dfrac{2}{2015\times2017}\)
d , \(\dfrac{5}{1\times3}+\dfrac{5}{3\times5}+...+\dfrac{5}{2015\times2017}\)
e , \(\dfrac{1}{1\times2}+\dfrac{1}{3\times4}+...+\dfrac{1}{2016\times2017}\)
b, 15/14 -5/11 +13/14 +0,5-6/11
7,5x:\(\left[9-6\frac{13}{21}\right]\)= 7. \(\left(\frac{3}{5}\right)\)
Cái này đúng hay sao??
\(B=\left|157\dfrac{13}{27}-273\dfrac{7}{19}\right|-96\dfrac{14}{27}+15\dfrac{12}{19}\)\(B=\left|157\dfrac{13}{27}-273\dfrac{7}{19}\right|-96\dfrac{14}{27}+15\dfrac{12}{19}\)
so sánh
a)9^20......27^13
b)2^21.......3^14