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

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

\(\frac{9^{14}\cdot25^5\cdot8^7}{18^{12}\cdot625^3\cdot24^3}=\frac{\left(3^2\right)^{14}\cdot\left(5^2\right)^5\cdot\left(2^3\right)^7}{\left(3^2\cdot2\right)^{12}\cdot\left(5^4\right)^3\cdot\left(3\cdot2^3\right)^3}\)

\(=\frac{3^{28}\cdot5^{10}\cdot2^{21}}{3^{24}\cdot2^{12}\cdot5^{12}\cdot3^3\cdot2^9}=\frac{3^{28}\cdot5^{10}\cdot2^{21}}{3^{25}\cdot5^{12}\cdot2^{21}}=\frac{3^3}{5^2}=\frac{27}{25}\)

\(\frac{9^{14}}{18^{12}}.\frac{25^5}{625^3}.\frac{8^7}{24^3}\)

\(=\frac{9^{14}}{\left(9.2\right)^{12}}.\frac{25^5}{25^6}.\frac{8^7}{\left(8.3\right)^3}\)

\(=\frac{9^{14}}{9^{12}.2^{12}}.\frac{1}{25}.\frac{8^7}{8^3.3^3}\)

\(=\frac{9^2}{2^{12}}.\frac{1}{25}.\frac{8^4}{3^3}\)

\(=\frac{81}{4096}.\frac{1}{25}.\frac{4096}{27}\)

\(=\frac{81}{4096}.\frac{4096}{27}.\frac{1}{24}=3.\frac{1}{24}=\frac{3}{24}\)

**** **** ****

Ngu voi ko biet lam

trả lời 

A=3/24

suy ra A=1/8

\(\frac{9^{14}.225^5.8^7}{18^{12}.625^3.24^3}=\frac{\left(3^2\right)^{14}.\left(3^2.5^2\right)^5.\left(2^3\right)^7}{\left(3^2.2\right)^{12}.\left(5^4\right)^3.\left(3.2^3\right)^3}=\frac{3^{28}.3^{10}.5^{10}.2^{21}}{3^{24}.2^{12}.5^{12}.3^3.2^9}=\frac{3^{38}.5^{10}.2^{21}}{3^{27}.2^{21}.5^{12}}=\frac{3^{11}}{5^2}\)

\(\frac{9^9\cdot225^5\cdot8^7}{18^{12}\cdot625^3\cdot24^3}=\frac{9^9\cdot\left(\left(3\cdot5\right)^2\right)^5\cdot8^7}{\left(9\cdot2\right)^{12}\cdot\left(\left(5^2\right)^2\right)^3\cdot\left(8\cdot3\right)^3}\)

\(=\frac{1}{9^3\cdot2^{12}}\cdot\frac{9^5\cdot5^{10}}{5^{12}}\cdot\frac{8^7}{8^3\cdot3^3}\)

\(=\frac{9^2\cdot8^4}{2^{12}\cdot5^2\cdot3^3}\)

\(=\frac{9\cdot\left(2^4\right)^3}{\left(2^4\right)^3\cdot5^2}\)

\(=\frac{9}{25}\)

a)\(\frac{\text{3600−75}}{\text{8400−105}}=\frac{3.1200-3.25}{7.1200-7.25}=\frac{3.\left(1200-25\right)}{7.\left(1200-25\right)}=\frac{3}{7}\)

b) \(\frac{9^{14}.25^5.8^2}{18^{12}.625^3.24^3}=\frac{\left(3^2\right)^{14}.\left(5^2\right)^5.\left(2^3\right)^7}{\left(2.3^2\right)^{12}.\left(5^4\right)^3.\left(2^3.3\right)^3}=\frac{3^{28}.5^{10}.2^{21}}{2^{12}.3^{24}.5^{12}.2^9.3^3}=\frac{3^{28}.5^{10}.2^{21}}{2^{21}.3^{27}.5^{12}}=\frac{3}{5^2}=\frac{3}{25}\)

c) \(C=\frac{1+3+5+...+19}{21+23+25+...+39}=\frac{\left(1+19\right).19:2}{\left(21+39\right).19:2}=\frac{190}{570}=\frac{1}{3}\)

c)

C = 1+3+5+...+1921+23+25+...+39

Số số hạng của tử là : ( 19 -1 ):2 + 1= 10 số

Số số hạng của mẫu là : ( 39 - 21 ) : 2 +1 = 10 số

Tổng các số hạng của tử là : ( 1 + 19 ) x 10 : 2 = 100

Tổng các số hạng của mẫu là : ( 21 + 39 ) x 10 : 2 = 300

Vậy C = 100/300 = 1 / 3

Mik làm mỗi ý C) thui . Sorry nha ! Nhớ tik

Ta có: \(\frac{9^9.225^5.8^7}{18^{12}.625^3.24^3}\)=\(\frac{\left(3^2\right)^9.\left(25.3^2\right)^5.\left(2^3\right)^7}{\left(2.3^2\right)^{12}.\left(25^2\right)^3.\left(3.8\right)^3}\)

=\(\frac{3^{18}.25^5.3^{10}.2^{21}}{2^{12}.3^{24}.25^6.3^3.2^9}\)

=\(\frac{3^{28}.25^5.2^{21}}{3^{27}.25^6.2^{21}}\)=\(\frac{3}{25.}\)