\(125^4:5^8\)

\(=\left(5^3\right)^4:5^8\)

\(=5^{12}:5^8\)

\(=5^{12-8}\)

\(=5^4\)

\(=625\)

`@` `\text {Ans}`

`\downarrow`

`100^6 * 1000^5 * 10000^3`

`= (10^2)^6 * (10^3)^5 * (10^4)^3`

`= 10^12 * 10^15 * 10^12`

`=`\(10^{12+15+12}=10^{39}\)

\(=10^{12}\cdot10^{15}\cdot10^{12}=10^{39}\)

X-31=5 NGŨ 2

ngũ hay mũ thế bn?

tìm n thoả mãn 5n+14\(⋮\)n+2

có bạn nào giúp mình ko

Ta có:A=\(2+2^2+2^3+...+2^{60}\)

+)A=\(2.\left(1+2+2^2+...+2^{59}\right)\)

\(\Rightarrow\)\(A⋮2\)

+)A=\(\left(2+2^2\right)+\left(2^3+2^4\right)+...+\left(2^{59}+2^{60}\right)\)

   A=\(2.\left(1+2\right)+2^3.\left(1+2\right)+...+2^{59}.\left(1+2\right)\)

   A=\(2.3+2^3.3+...+2^{59}.3\)

\(\Rightarrow A⋮3\)

Mà 2;3 là 2 số nguyên tố cùng nhau

\(\Rightarrow A⋮2.3\)

\(\Rightarrow A⋮6\)

Học tốt nha!!!

A=2+2^2+2^3+2^4+2^5+....+2^60

2A=2.[2+2^2+2^3+2^4+2^5+....+2^60]

2A=2.2+2^2.2+2^3.2+2^4.2+2^5.2+....+2^60.2

2A=2^2+2^3+2^4+2^5+2^6+....+2^61

2A-A=[2^2+2^3+2^4+2^5+2^6+....+2^61]-[2+2^2+2^3+2^4+2^5+....+2^60]

A=2^61-2 chia hết cho 6

đến đây dễ r bn tự giải đi nhé

=81*(27+9^15):(3^5+3^32)

\(=\dfrac{3^4\cdot\left(3^3+3^{30}\right)}{3^5+3^{32}}=\dfrac{3^7\left(1+3^{27}\right)}{3^5\left(1+3^{27}\right)}=\dfrac{3^7}{3^5}=9\)