Cho hỏi là dùng thì gì vậy ?

Help me 

P1: Two boys walked on the walkside and they saw something on that pavement. Not any things, just monet.

P2: One of the boys picked up the money and they suggested to buy something.

P3: They weren't know what to buy so they bought ice-cream

(Chúc bạn học tốt)

Đặt d=UCLN(2n+5;3n+7)

Ta có:

2n+5chia hết cho d =>3(2n+5)=6n+15 chia hết cho d

3n+7chia hết cho d =>2(3n+7)=6n+14 chia hết cho d

=> (6n+15)-(6n+14)=1 chia hết cho d

=>d=1

vậy UCLN(2n+5;3n+7)=1 =>UC(2n+5;3n+7)=1

CHÚC BN LÀM BÀI TỐT NHÉ

2n+5 va 3n+7

=(2n+5;n+2)

=(n+3;n+2)

=(1;n+2)

Vay uc(2n+5;3n+7)=1

kể về 1 việc tốt mà em đã  làm

Mk wen bn đuk ko ta???

ok bn

Tiếc cái nick kia quá đi ak !!!!!!!!!!!!!! Bùn rùi rụi !!!!!!!!!!!

\(2.16\ge2^n>4\)

\(2.2^4\ge2^n>2^2\)

\(2^5\ge2^n>2^2\)

=> \(n\in\left\{3,4,5\right\}\)

Vậy: \(n\in\left\{3,4,5\right\}\)

2 It take more hours to travel by train than to travel

6 The bus run more frequently than the trains

diện h caí bìa để làm cái hộp là:                                                                                                                                                                            6*6*6=216(cm2)                                                                                                                                                                                                        đ/s:..(tự đáp số)

=6*6*6

=126 cm2

a)49.7.7³

=7².7¹.7³

=7⁶

b)9⁸:3²

9⁸=(3²)⁸

=3¹⁶:3²

=3¹⁴

Chúc em học tốt^^

A/14 :3/7 =2

\(\frac{A}{14}=2x\frac{3}{7}\)

\(\frac{A}{14}=\frac{6}{7}\)

\(\frac{A}{14}=\frac{12}{14}\)

\(A=12\)

\(\frac{A}{14}\div\frac{3}{7}=2\)

\(\frac{A}{14}=2\times\frac{3}{7}\)

\(\frac{A}{14}=\frac{6}{7}\)

\(\frac{A}{14}=\frac{12}{14}\)

\(\Rightarrow A=12\)

5 That is the farthest distance i have ever run

6 It was the worst mistake I have ever made

5 That's the furthest (or farthest) I've ever run.

6 It is/was the worst mistake I've ever made.

5. That run .... ( mình ko hiểu đề )

6. It make the worst mistake