Question

[KAl(SO4)2·12H2O]

Tính: \(A=\frac{3^6.45^5-15^3.5^9}{27^4.25^3+45^6}\)

Các anh, chị cứu em :<

Answer 1

[zZz Cool Kid_new zZz]

\(\frac{3^6\cdot45^5-15^3\cdot5^9}{27\cdot25^3+45^6}\)

\(=\frac{3^6\cdot3^{10}\cdot5^5-3^3\cdot5^3\cdot5^9}{3^{12}\cdot5^6+5^6\cdot3^{12}}\)

\(=\frac{3^{16}\cdot5^5-3^3\cdot5^{12}}{2\cdot3^{12}\cdot5^6}=\frac{3^3\cdot5^5\left(3^{13}-5^7\right)}{2\cdot3^{12}\cdot5^6}=\frac{3^{13}-5^7}{2\cdot3^9\cdot5}\)

\(=\frac{3^{13}}{2\cdot3^9\cdot5}-\frac{5^7}{2\cdot3^9\cdot5}=\frac{81}{10}-\frac{5^6}{2\cdot3^9}\)

haiz!đến đây tịt!có sai đề ko bạn?

Answer 2

[kudo shinichi]

\(A=\frac{3^6.45^5-15^3.5^9}{27^4.25^3+45^6}\)

\(A=\frac{3^6.\left(3^2.5\right)^5-\left(3.5\right)^3.5^9}{\left(3^3\right)^4.\left(5^2\right)^3+\left(3^2.5\right)^6}\)

\(A=\frac{3^6.3^{10}.5^5-3^3.5^3.5^9}{3^{12}.5^6+3^{12}.5^6}\)

\(A=\frac{3^{16}.5^5-3^3.5^{12}}{3^{12}.5^6+3^{12}.5^6}\)

\(A=\frac{3^3.5^5.\left(3^{13}-5^7\right)}{2.3^{12}.5^6}\)

\(A=\frac{3^{13}-5^7}{2.3^9.5}\)

Có gì đó sai sai