\(\dfrac{3}{5}\) \(\times\) ( \(\dfrac{5}{2}\) - \(\dfrac{10}{3}\)) - \(\dfrac{5}{8}\): ( \(\dfrac{1}{4}\) - \(\dfrac{2}{3}\))

\(\dfrac{3}{5}\) \(\times\) \(\dfrac{5}{2}\) - \(\dfrac{3}{5}\) \(\times\) \(\dfrac{10}{3}\) - \(\dfrac{5}{8}\): (-\(\dfrac{5}{12}\))

= \(\dfrac{3}{2}\) - 2 + \(\dfrac{3}{2}\)

= (\(\dfrac{3}{2}\) + \(\dfrac{3}{2}\)) - 2

= 3 - 2

= 1

$\frac{3}{5}\times (\frac{5}{2}-\frac{10}{3})-\frac{5}{8}:(\frac{1}{4}-\frac{2}{3})$

$=\frac{3}{5}\times (\frac{15}{6}-\frac{20}{6})-\frac{5}{8}:(\frac{3}{12}-\frac{8}{12})$

$=\frac{3}{5}\times (-\frac{5}{6})-\frac{5}{8}:(-\frac{5}{12})$

$=-\frac{1}{2}-(-\frac{3}{2})$

$=-\frac{1}{2}+\frac{3}{2}$

$=\frac{2}{2}$

$=1$

\(\frac{-4}{7}+\left(\frac{-2}{3}+\frac{4}{7}\right)\)

\(=\frac{-4}{7}+\frac{-2}{3}+\frac{4}{7}\)

\(=\left(\frac{-4}{7}+\frac{4}{7}\right)+\frac{-2}{3}\)

\(=0+\frac{-2}{3}=\frac{-2}{3}\)

~ Hok tốt ~

\(\frac{-3}{10}.\frac{5}{12}+\frac{-3}{10}.\frac{7}{12}+5\frac{3}{10}\)

\(=\frac{-3}{10}.\frac{5}{12}+\frac{-3}{10}.\frac{7}{12}+\frac{53}{10}\)

\(=\frac{-3}{10}.\left(\frac{5}{12}+\frac{7}{12}\right)+\frac{53}{10}\)

\(=\frac{-3}{10}.1+\frac{53}{10}\)

\(=\frac{-3}{10}+\frac{53}{10}=\frac{50}{10}=5\)

~ Hok tốt ~

Cả 2 dãy mỗi dãy nhóm 2 số lại

a ) 2 - 3 + 4 - 5 + 6 - 7 + 8 - ... + 209 + 210

( 2 - 3 ) + ( 4 - 5 ) + ( 6 - 7 ) + ( 8 - 9 ) + ... + ( 207 - 208 ) + ( 209 + 210 )

= - 1 + ( -1 ) + ( - 1 ) + ( - 1 ) + ... + ( - 1 ) + 219

Bài này hơi kì kì sao ấy !

Đây là toán lớp 6 mà lại là tính hợp lí, thuộc vào chương số nguyên nên mấy bé lớp 5,4,3,2,1 đừng dại gì mà giải nhé 

\(a,-\frac{4}{7}+\left(-\frac{2}{3}+\frac{3}{7}\right)=-\frac{4}{7}-\frac{2}{3}+\frac{3}{7}=-\frac{4}{7}+\frac{3}{7}-\frac{2}{3}=-\frac{1}{7}-\frac{2}{3}=-\frac{17}{21}\)

\(b,-\frac{3}{10}\cdot\frac{5}{12}+-\frac{3}{10}\cdot\frac{7}{12}+5\cdot\frac{3}{10}=\frac{3}{10}\cdot-\frac{5}{12}+\frac{3}{10}\cdot-\frac{7}{12}+5\cdot\frac{3}{10}=\frac{3}{10}\cdot\left(-\frac{5}{12}-\frac{7}{12}+5\right)\)

\(=\frac{3}{10}\cdot4=\frac{6}{5}\)

ti ck nha

đúng đó

xin đó

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a, -4/7 + (-2/3 + 3/7 )

= -4/7 + (-2/3) + 3/7

= -4/7 + 3/7 + (-2/3)

= -1/7 + -14/21

= -3/21 + -14/21

= -17/21

b, -3/10 . 5/12 + -3/10 . 7/12 + 5. - 3/10

-3/10.(5/12 + 7/12 + 60/12)

-3/10.6

-18/10= -9/5

\(=\dfrac{2^{36}.3^{36}\left(2.5^2.5^{40}-2.5.5^{34}\right)}{2^{30}.3^{30}.5^{30}.2^4.5^4\left(2^2.5^2.3^5.5^5-2^2.3^5\right)}=\dfrac{2^{36}.3^{36}\left(2.5^{42}-2.5^{35}\right)}{2^{34}.3^{30}.5^{34}\left(2^2.3^5.5^7-2^2.3^5\right)}\)

\(=\dfrac{2^2.3^6.2.5^{35}\left(5^7-1\right)}{2^2.3^5\left(5^7-1\right)}=3.2.5^{35}=6.5^{35}\)

\(\dfrac{4^{10}.9^6+3^{12}.8^5}{6^{13}.4-2^{16}.3^{12}}\)

\(=\dfrac{\left(2^2\right)^{10}.\left(3^2\right)^6+3^{12}.\left(2^3\right)^5}{\left(2.3\right)^{13}.2^2-2^{16}.3^{12}}\)

\(=\dfrac{2^{20}.3^{12}+3^{12}.2^{15}}{2^{13}.3^{13}.2^2-2^{16}.3^{12}}\)

\(=\dfrac{2^{20}.3^{12}+3^{12}.2^{15}}{2^{15}.3^{13}-2^{16}.3^{12}}\)

\(=\dfrac{2^{15}.3^{12}.\left(2^5+1\right)}{2^{15}.3^{13}.\left(3-2\right)}\)

\(=\dfrac{2^5+1}{3-2}\)

\(=\dfrac{32+1}{1}=33\)

^{1/2 + 2/3 - 3/4 * 4/5 * 5/6 * 6/7 * 7/8 * 8/9 *...* 29/30 : 6/10}

^{= 1/2 + 2/3 - 1/10 : 6/10}

^{= 1/2 + 2/3 - 1/6}

^{= 1}

\(\frac{4^{10}.9^6+3^{12}.8^5}{6^{13}.4-2^{16}.3^{12}}\)

\(=\frac{\left(2^2\right)^{10}.\left(3^2\right)^6+3^{12}.\left(2^3\right)^5}{\left(2.3\right)^{13}.2^2-2^{16}.3^{12}}\)

\(=\frac{2^{20}.3^{12}+3^{12}.2^{15}}{2^{13}.3^{13}.2^2-2^{16}.3^{12}}\)

\(=\frac{2^{20}.3^{12}+3^{12}.2^{15}}{2^{15}.3^{12}.3-3^{12}.2^{16}}\)

\(=\frac{2^4}{3}\)