a) 2012 - ( 304 + 2012 ) + ( 2013 + 304 )

= 2012 - 304 - 2012 + 2013 + 304 

= 2012 + ( - 304 ) + ( - 2012 ) + 2013 + 304

= [ 2012 + ( - 2012 ) ] + [ ( - 304 ) + 304 ] + 2013

= 0 + 0 + 2013

= 2013

b) \(\frac{9^{14}.25^5.8^7}{18^{12}.625^3.24^3}\)

\(=\frac{\left(3^2\right)^{14}.\left(5^2\right)^5.\left(2^3\right)^7}{\left(3^2.2\right)^{12}.\left(5^4\right)^3.\left(2^3.3\right)^3}\)

\(=\frac{3^{28}.5^{10}.2^{21}}{3^{24}.2^{12}.5^{12}.2^9.3^3}\)

\(=\frac{3^{28}.5^{10}.2^{21}}{3^{27}.5^{12}.2^{21}}\)

\(=\frac{3}{5^2}=\frac{3}{25}\)

a) 2012 - ( 304 + 2012 ) + (2013 + 304 )

= 2012 - 304 +2012 + 2013 + 304

= ( 2012 - 2012 ) + ( 304 + 304 ) + 2013

= 0 + 608 + 2013

= 2621

Chờ một chút để minh suy nghĩ 

ok bạn

2012-304-2012+2013+304

=(2012-2012)+(304-304)+2013

=0+0+2013

=2013

2012 - ( 304 + 2012 ) + ( 2013 + 304 )

= 2012 - 2316 + 2317

= -304 + 2317

= 2013

20112-(304+2012)+(2013+304)

=20112-304-2012+2013+304

=20112+(-2012+2013)+(-304+304)

=20112+1+0=20113

\(\frac{9^{14}.25^5.8^7}{18^{12}.625^3.24^3}=\frac{\left(3^2\right)^{14}.25^5.\left(2^3\right)^7}{2^{12}.\left(3^2\right)^{12}.\left(25^2\right)^3.\left(2^3\right)^3.3^3}=\)\(\frac{3^{28}.25^5.2^{21}}{2^{12}.2^9.3^{24}.3^3.25^6}=\frac{3^{28}.25^5.2^{21}}{2^{21}.3^{27}.25^6}\)\(=\frac{3}{25}\)

\(\left(-48\right)\cdot72+36\left(-304\right)\)

\(=36\left(-48\cdot2-304\right)\)

\(=36\cdot\left(-400\right)\)

\(=-14400\)

\(48\left(-21\right)-142\left(-24\right)\)

\(=24\left[2\left(-21\right)+142\right]\)

\(=24\cdot100\)

\(=2400\)

\(304\times3+304\times5+304\times2\)

\(=304\times\left(3+5+2\right)\)

\(=304\times10\)

\(=3040\)

$Ta\; có:304\times 3+304\times 5+304\times 2$

$=304\times \left(3+5+2\right)$

$=304\times 10$

$=3040$

kết quả là:3040

= 164 196

a) 24680 + 752 × 304 = 24680 + 228608

= 253288

b) 135790 – 12126 : 258 = 135790 – 47

= 135743

( − 48 ) .72 + 36. ( − 304 ) = ( − 48 ) .2.36 + 36. ( − 304 ) = ( − 96 ) .3 + 36. ( − 304 )