\(x\cdot2^2=2^7\)

\(\Rightarrow x=\dfrac{2^7}{2^2}\)

\(\Rightarrow x=2^{7-2}\)

\(\Rightarrow x=2^5\)

\(\Rightarrow x=32\)

\(\left(x-1\right).3=15\\ =>x-1=5\\ =>x=6\)

\(20:\left(x+1\right)-3=2\\ =>20:\left(x+1\right)=5\\ =>x+1=4\\ =>x=3\)

\(\left(x-1\right).3=15\)

\(x-1=15:3\)

\(x-1=5\)

\(x=5+1\)

\(x=6\)

Vậy \(x=6\)

\(20:\left(x+1\right)-3=2\)

\(\left(x+1\right)-3=20:2\)

\(\left(x+1\right)-3=10\)

\(x+1=10-3\)

\(x+1=7\)

\(x=7-1\)

\(x=6\)

Vậy \(x=6\)

\(\left(1+5+5^2\right)+\left(5^3+5^4+5^5\right)+...+\left(5^{402}+5^{403}+5^{404}\right)\\ =31+5^3.\left(1+5+5^2\right)+...+5^{402}.\left(1+5+5^2\right)\\ =31+5^3.31+...+5^{402}.31\\ =31.\left(1+5^3+...+5^{402}\right)⋮31\left(DPCM\right)\)

dpcp là gì vậy ạ

\(x^3-20=7\\ =>x^3=27=3^3\\ =>x=3\)

`x^3-20=7`

`=>x^3=7+20`

`=>x^3=27`

`=>x^3=3^3`

`=>x=3`

Giúp minh với nha 😉

Vì \(m,n\in A\) \(\Rightarrow B\in A\)

Vậy \(m=7\) hoặc \(m=5\)

\(n=5\) hoặc \(n=7\)

\(33\times77+66\times77+77\)

\(=77\times\left(33+66+1\right)\)

\(=77\times100\)

\(=7700\)

1+3+5+7+...+2013
số số hang : (2013-1):2+1=1007
Vậy Ta có tổng là : (2013+1).1007:2=1014049

Số số hạng:

(2013 - 1) : 2 + 1 = 1007 (số)

1 + 3 + 5 + 7 + ... + 2013

= (2013 + 1) . 1007 : 2

= 1014049

`#3107`

`12341234 . 5678 - 56785678 . 1234`

`= 1234.10001.5678 - 5678.10001.1234 `

`= 10001.(1234.5678 - 5678.1234)`

`= 10001.0`

`= 0`

Số lẻ lớn nhất có 6 chữ số khác nhau là: 987653

987653

                                                 𝓖𝓲𝓪̉𝓲:

𝓖𝓸̣𝓲 𝓼𝓸̂́ 𝓽𝓾̛̣ 𝓷𝓱𝓲𝓮̂𝓷 𝓷𝓱𝓸̉ 𝓷𝓱𝓪̂́𝓽 𝓬𝓸́ 𝓷𝓪̆𝓶 𝓬𝓱𝓾̛̃ 𝓼𝓸̂́ 𝓬𝓪̂̀𝓷 𝓽𝓲̀𝓶 𝓵𝓪̀ 𝔁.

𝓣𝓪 𝓬𝓸́: \(x:8\)  𝓭𝓾̛ 7 

            \(x:9\)  𝓭𝓾̛ 7 

            \(x:10\)  𝓭𝓾̛ 7

            \(x:11\)  𝓭𝓾̛ 7

            \(x:12\)  𝓭𝓾̛ 7

\(\Rightarrow x-7⋮8,9,10,11,12\Rightarrow x-7\in BCNN\left(8;9;10;11\right)\)

𝓣𝓪 𝓽𝓲̀𝓶 𝓑𝓒𝓝𝓝(8;9;10;11;12)

\(8=2^3;9=3^2;10=2.5;11=11;12=2^2.3\)

\(\Rightarrow BCNN\left(8;9;10;11;12\right)=2^3.3^2.5.11=3960\)

\(\Rightarrow BCNN\left(8;9;10;11;12\right)\in BC\left(3960\right)=\left\{0;3960;7920;11880;...\right\}\)

𝓜𝓪̀ 𝔁 𝓼𝓸̂́ 𝓽𝓾̛̣ 𝓷𝓱𝓲𝓮̂𝓷 𝓷𝓱𝓸̉ 𝓷𝓱𝓪̂́𝓽 𝓬𝓸́ 𝓷𝓪̆𝓶 𝓬𝓱𝓾̛̃ 𝓼𝓸̂́ 𝓷𝓮̂𝓷 𝔁 𝓵𝓪̀ 11880

𝓥𝓪̣̂𝔂 𝓼𝓸̂́ 𝓬𝓪̂̀𝓷 𝓽𝓲̀𝓶 𝓵𝓪̀ 11880