b) \(\dfrac{7.12^3+64.27}{4^6.3^4}\)

a) \(\dfrac{7.5^9.\left(3^2\right)^5}{15^{10}}\)=\(\dfrac{7.5^9.3^{10}}{15^{10}}\)=\(\dfrac{7.5^9.3^9.3}{15^{10}}\)=\(\dfrac{7.15^9.3}{15^{10}}\)\(\dfrac{7.3}{15}=\dfrac{7}{5}\)

\(\dfrac{7.\left(4.3\right)^3+4^3.3^3}{4^6.3^4}\)=\(\dfrac{4^3.3^3\left(7+1\right)}{4^6.3^4}=\dfrac{4^3.3^3.2^3}{4^6.3^4}\)=\(\dfrac{2^3}{4^3.3^1}=\dfrac{2^3}{2^3.2^3.3}=\dfrac{1}{2^3.3}=\dfrac{1}{24}\)

\(=\dfrac{2^{19}\cdot3^9+2^{18}\cdot3^9\cdot5}{2^{19}\cdot3^9+2^{20}\cdot3^{10}}=\dfrac{2^{18}\cdot3^9\cdot\left(2+5\right)}{2^{19}\cdot3^9\cdot7}=\dfrac{1}{2}\)

Tử số= 2^19.9^3.3^3 + 5.3.2^9.2^9.9^4 
= 2^19.9^3.3^3 + 5.3.2^18.9.9^3 
= 2^19.9^3.3.3^2 + 5.3.2^18.3^2.9^3 
= 2^18.9^3.3^2(2 + 5.) (đặt nhân tử chung) 
=7.2^18.9^3.3^2 
=7.2^18.9.9.9.3^2 
=7.2^18.3^2.3^2.3^2.3^2 
=7.2^18.3^8 
Mẫu số= 6^9.2^10 + 6^10.2^10 
= 6^9.2^10 + 6^10.2^10 
=6^9.2^10(1+6) 
=7.6^9.2^10. 
=7.2^9.3^9.2^10 
=7.2^19.3^9 
Lấy tử số chia mẫu số ta được : 1/2.3 = 1/6

tick nhé bạn

gọn các phân số sau:

a) 7.5⁹.9⁵ / 15¹⁰

b) 3.7.8.13/ 14.15.26

/ là gạch ngang trong phân số 

Giải chi tiết giúp mình

a)=35

b)=2/5

k nha

a)=35

b)=2/5

k nha

là 1 nha bạn

\(\frac{2^{19}.27^3+15.4^9.9^4}{6^9.2^{10}+12^{10}}\)

\(=\frac{2^{19}.\left(3^3\right)^3+3.5.\left(2^2\right)^9.\left(3^2\right)^4}{\left(2.3\right)^9.2^{10}+\left(2^2.3\right)^{10}}\)

\(=\frac{2^{19}.3^9+3.5.2^{18}.3^8}{2^9.3^9.2^{10}+2^{20}.3^{10}}\)

\(=\frac{2^{19}.3^9.\left(1+5\right)}{2^{19}.3^9.\left(1+2.3\right)}=\frac{6}{7}\)

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