1) Kinh 2) Tày 3)Thái 4) Hoa 5) Khơ-me 6) Mường 7) Nùng 8) HMông 9) Dao 10) Gia-rai 11) Ngái 12) Ê-đê 13) Ba na 14) Xơ-Đăng 15) Sán Chay 16) Cơ-ho 17) Chăm 18) Sán Dìu 19) Hrê 20) Mnông 21) Ra-glai 22) Xtiêng 23) Bru-Vân Kiều 24) Thổ 25) Giáy 26) Cơ-tu 27) Gié Triêng 28) Mạ 29) Khơ-mú 30) Co 31) Tà-ôi 32) Chơ-ro 33) Kháng 34) Xinh-mun 35) Hà Nhì 36) Chu ru 37) Lào 38) La Chí 39) La Ha 40) Phù Lá 41) La Hủ 42) Lự 43) Lô Lô 44) Chứt 45) Mảng 46) Pà Thẻn 47) Co Lao 48) Cống 49) Bố Y 50) Si La 51) Pu Péo 52) Brâu 53) Ơ Đu 54) Rơ măm

\(1+1+2+3+4+5+6+7+8+9+10\cdot0=46\)

Công thức tính diện tích hình bình hành là \(S=a\cdot h\) mà

Sao lại có 2 đáy?

\(2\cdot5^2+3:71^0-54:3^2\)

\(=2\cdot25+3:1-54:9\)

\(=50+3-6\) \(=53-6=47\)

8,556kg = 0,08556 tạ

Ta có: 2a + 3b ⋮ 17

⇒ 30(2a + 3b) ⋮ 17

⇒ 60a + 90b ⋮ 17

⇒ 51a + 9a + 85b + 5b ⋮ 17

⇒ (51a + 85b) + (9a + 5b) ⋮ 17

⇒ 17(3a + 5b) + (9a + 5b) ⋮ 17

Vì 17(3a + 5b) ⋮ 17 nên (9a + 5b) ⋮ 17

Vậy 9a + 5b ⋮ 17

sửa câu trl thì ko sửa đc bn nhé

vào cập nhật thôi

Gọi ƯCLN(2n + 5, 3n +7) = d (d ϵ N*)

\(\Rightarrow\left\{{}\begin{matrix}\left(2n+5\right)⋮d\\\left(3n+7\right)⋮d\end{matrix}\right.\Rightarrow\left\{{}\begin{matrix}3\left(2n+5\right)⋮d\\2\left(3n+7\right)⋮d\end{matrix}\right.\Rightarrow\left\{{}\begin{matrix}\left(6n+15\right)⋮d\\\left(6n+14\right)⋮d\end{matrix}\right.\)

=> [(6n + 15) - (6n + 14)] ⋮ d => 1 ⋮ d

    Mà d ϵ N* 

=> ƯCLN(2n + 5, 3n + 7) = 1

Vậy (2n + 5, 3n + 7) là 2 số nguyên tố cùng nhau

9999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999+1= 9999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999+1