\(\left(5^2\times2^3-7^3\times2\right)\div2\times6-7\div2^5\)

\(=\left(25\times8-343\times2\right)\div2\times6-7\div32\)

\(=\left(200-686\right)\div2\times6-7\div32\)

\(=-486\div2\times6-7\div32\)

\(=-1458-0,21875\)

\(=-1458,21875\)

\(\left(5^2.2^3-7^3.2\right):\left(2.6-7:2^5\right)\\ =\left(25.8-343.2\right):\left(12-7:32\right)\\ =\left(200-686\right):\left(12-\dfrac{7}{32}\right)\\ =-486:\dfrac{377}{32}=-486.\dfrac{32}{377}=-\dfrac{15552}{377}\)

(5^2*2^3-7^3*2):2*6-7:2^5

=(25*8-343*2):3-7/32

=-162-7/32=-5191/32

\(a,\)\(\frac{2^5\times3^{12}\times7^8}{2^7\times3^{10}\times7^9}=\frac{3^2\times\left(2^5\times3^{10}\times7^8\right)}{2^2\times7\times\left(2^5\times3^{10}\times7^8\right)}\)\(=\frac{3^2}{2^2\times7}=\frac{9}{28}\)

\(b,\)Tương tự

$\textbf{a)}$

$\dfrac{2^5\cdot3^{12}\cdot7^8}{2^7\cdot3^{10}\cdot7^9}$

$=\dfrac{3^{12-10}}{2^{7-5}\cdot7^{9-8}}$

$=\dfrac{3^2}{2^2\cdot7}$

$=\dfrac{9}{28}.$

\(4^2\cdot120-4^3\cdot17+4^2\cdot34\)

\(=4^2\left(120-4\cdot17+34\right)\)

\(=16\left(120-68+34\right)\)

\(=16\cdot86=1088\)

\(7^3\cdot9+3^2\cdot7^4-45\cdot539\)

\(=7^3\cdot9+9\cdot7^4-45\cdot7^2\cdot11\)

\(=7^2\left(7\cdot9+9\cdot7^2-45\cdot11\right)\)

\(=49\left(63+9\cdot49-495\right)\)

\(=49\left(63+441-495\right)\)

\(=49\cdot9=441\)

71 nhé em

học tốt

TL

71

HT

$\textbf{A)}$

$\dfrac{2^{10}-2^7\cdot9}{2^7-2^4\cdot9}$

$=\dfrac{2^7(2^3-9)}{2^4(2^3-9)}$

$=\dfrac{2^7}{2^4}$

$=2^3$

$=8.$

$\textbf{B)}$

$\left(\dfrac{27^4}{9^5}+\dfrac{625^3}{125^4}\right)-2^3$

$=\left(\dfrac{(3^3)^4}{(3^2)^5}+\dfrac{(5^4)^3}{(5^3)^4}\right)-8$

$=(3^{12-10}+5^{12-12})-8$

$=(3^2+1)-8$

$=10-8$

$=2.$

sai

sai

đúng

sai

\(37\left(3+7\right)=3^3+7^3\)

\(37\cdot10=27+343\)

\(370=370\)(thảo mãn

=>đúng

vậy 37(3+7)=3^3+7^3