Question

[Huyền Nguyễn]

Chứng minh: 2^17+2^14 chia hết cho 9 

Chứng minh 15^3-25^2 chia hết cho 11

Answer 1

[Full Moon]

Ta có: \(2^{17}+2^{14}\)

\(=2^{14}\left(2^3+1\right)=2^{14}\times9⋮9\)

\(15^3-25^2\)

\(=3^3.5^3-5^4\)

\(=5^3\left(27-5\right)=5^3.2.11⋮11\)

Answer 2

[zZz Cool Kid_new zZz]

\(2^{17}+2^{14}=2^{14}\left(2^3+1\right)=2^{14}\cdot9\Rightarrow2^{17}+2^{14}⋮9\)