\(\frac{677.874+251}{678.874-623}\)

\(=\frac{591698+251}{592572-623}\)

\(=\frac{591949}{591949}=1\)

\(\frac{677\times874+251}{678\times874-623}\)\(=\frac{677\times874+251}{\left(677+1\right)\times874-623}\)\(=\frac{677\times874+251}{677\times874+1\times874-623}\)\(=\frac{677\times874+251}{677\times874+874-623}=\frac{677\times874+251}{677\times874+251}=1\)

\(\frac{677.874+251}{678.874-623}\)

\(=\frac{677.874+251}{\left(677+1\right).874-623}\)

\(=\frac{677.874+251}{677.874-1.874-623}\)

\(=\frac{677.874+251}{677.874+874-623}\)

\(=\frac{677.874+251}{677.874+251}\)

\(=1\)

Hok tốt

(677*874+251) : (678*874-623)=1

Mình không biết đúng hay sai nữa.Thông cảm

677*874+251=591949

678*874-623=591949

=591949

B = (1999x1998 + 1998x1997)x(1+1/2: 1 1/2 - 11/3)

B = (1999x1998 + 1998x1997)x(1+1/2:3/2-4/3)

B = (1999x1998 +1998 x1997) x (1+1/2x2/3 - 4/3)

B = (1999 x 1998 + 1998 x 1997) x(1+1/3 - 4/3)

B = (1999 x 1998 + 1998 x 1997) x (4/3 - 4/3)

B = (1999 x 1998 + 1998 x 1997) x 0

B = 0

\(\left(\frac{57575757}{42424242}+\frac{57575757}{56565656}+\frac{57575757}{72727272}\right).18\)

\(=\left(\frac{57}{42}+\frac{57}{56}+\frac{57}{72}\right).18\)

\(=57.\left(\frac{1}{42}+\frac{1}{56}+\frac{1}{72}\right)x18\)

\(=57.\left(\frac{1}{6.7}+\frac{1}{7.8}+\frac{1}{8.9}\right)x18\)

\(=57x\left(\frac{1}{6}-\frac{1}{7}+\frac{1}{7}-\frac{1}{8}+\frac{1}{8}-\frac{1}{9}\right)x18\)

\(=57x\left(\frac{1}{6}-\frac{1}{9}\right)x18\)

=....................................................(Quan trọng nhất là máy tính. Hết thần thái rồi:V

ủa 23m2 94dm2=2394 đúng ko

\(=1\left(\frac{1}{2.3}+\frac{1}{3.4}+\frac{1}{4.5}+...+\frac{1}{9.10}\right)\)

\(=1\left(1-\frac{1}{2}+\frac{1}{2}-\frac{1}{3}+\frac{1}{3}-...+\frac{1}{9}-\frac{1}{10}\right)\)

\(=1-\frac{1}{10}\)

\(=\frac{9}{10}\)

1/2-1/10=2/5

Chúc bạn may mắn@

3995.7/1004.4

\(250\times12-\left(242+302\times2,5\right)\)

\(=3000-997\)

\(=2003\)