\(\left(2^{78}+2^{79}+2^{80}\right):\left(2^{77}+2^{76}+2^{75}\right)=\left(2^{78}.7\right):\left(2^{75}.7\right)=2^{78}:2^{75}=8\)

\(a;\frac{2^{78}+2^{79}+2^{80}}{2^{77}+2^{76}+2^{75}}=\frac{2^{78}\left(1+2+2^2\right)}{2^{75}\left(1+2+2^2\right)}=2^3=8\)

b) \(\frac{5^{56}+5^7}{5^{49}+1}=\frac{5^7\left(5^{49}+1\right)}{5^{49}+1}=5^7\)

=(2^78+79+80):(2^77+76+75)

=2²³⁷:2²²⁸

=2^237-228

=2⁹

=512

\(\left(2^{78}+2^{79}+2^{80}\right):\left(2^{77}+2^{76}+2^{75}\right)\)

\(=2^3\left(2^{75}+2^{76}+2^{77}\right):\left(2^{75}+2^{76}+2^{77}\right)\)

\(=2^3\)

\(=8\)

Bài làm:

\(\left(2^{78}+2^{79}+2^{80}\right)\div\left(2^{77}+2^{76}+2^{75}\right)\)

\(=\frac{2^{78}\left(1+2+2^2\right)}{2^{75}\left(2^2+2+1\right)}\)

\(=2^3=8\)

=(2⁷⁸+2⁷⁹+2⁸⁰):(2⁷⁷+2⁷⁶+2⁷⁵)
=2³

2⁷⁸ ( 1 + 2+ 4) : [ 2⁷⁵ ( 4 + 2 + 1)]

2^{78 :} 2⁷⁵ = 2³ = 8

2⁷⁸ ( 1 + 2+ 4) : [ 2⁷⁵ ( 4 + 2 + 1)]

2^{78 :} 2⁷⁵ = 2³ = 8

=2⁷⁸.(1+2+2²):2⁷⁵.(1+2+2²)

=2⁷⁸:2⁷⁵

=2³=8

a/ là 8

b/ là 3615924564

HỌC TỐT NHÉ 

NHỚ CHỌN CHO MÌNH NHÉ

Bạn ghi cách làm giúp mình được không

a)

\(=\frac{2^{78}\left(2^2+2+1\right)}{2^{75}\left(2^2+2+1\right)}\)

\(=\frac{2^{78}}{2^{75}}=2^3=8\)

b)

\(=\frac{3^{90}\left(3^3+1\right)}{3^{17}\left(3^{56}+1\right)}=\frac{3^{73}\left(3^3+1\right)}{3^{56}+1}\)

\(\frac{2^{78}\cdot\left(1+2+2^2\right)}{2^{75}\cdot\left(1+2+2^2\right)}=2^3=8\)