Question

[Trần Bảo Hân]

Giúp e câu bcd bài 2.

Answer 1

[Nguyễn Đức Trí]

b) \(\left(5^{22}.7-5^{21}.10\right):25^{11}\)

\(=5^{21}.\left(5.7-10\right):5^{22}\)

\(=5^{21}.25:5^{22}=5^{21}.5^2:5^{22}=5^{23}:5^{22}=5\)

c) \(\dfrac{3^6.15^5+9^3.15^6}{3^{10}.5^2.2^3}=\dfrac{3^6.3^5.5^5+3^6.3^6.5^6}{3^{10}.5^2.2^3}\)

\(=\dfrac{3^{11}.5^5+3^{12}.5^6}{3^{10}.5^2.2^3}=\dfrac{3^{11}.5^5\left(1+3.5\right)}{3^{10}.5^2.2^3}\)

\(=\dfrac{3^1.5^3.16}{2^3}=\dfrac{3^1.5^3.2^4}{2^3}=3.125.2=750\)

d) \(\dfrac{11.27^7.3^8-9^{15}}{\left(2.3^{14}\right)^2}=\dfrac{11.3^{21}.3^8-3^{30}}{2^2.3^{28}}=\dfrac{11.3^{29}-3^{30}}{2^2.3^{28}}\)

\(=\dfrac{3^{29}\left(11-3\right)}{2^2.3^{28}}=\dfrac{3^1.8}{2^2}=\dfrac{3.2^3}{2^2}=3.2=6\)

Answer 2

[Trần Bảo Hân]

  

Answer 3

[Trần Bảo Hân]

Đề bài đây nhé: 

\(b,\left(5^{22}\times7-5^{21}\times10\right)\div25^{11}\)

\(c,\dfrac{3^6\times15^5+9^3\times15^6}{3^{10}\times5^2\times2^3}\)

\(d,\dfrac{11\times27^7\times3^8-9^{15}}{\left(2\times3^{14}\right)^2}\)