A. Ta thấy : 132 chia hết cho 2; 50 chia hết cho 2 => 132 + 50 chia hết cho 2

B. Ta thấy : 375 ko chia hết cho 2; 16 chia hết cho 2 => 375 + 16 ko chia hết cho 2

C. Ta thấy : 220 chia hết cho 2; 18 chia hết cho 2 => 220 - 18 chia hết cho 2

D. Ta thấy 390 chia hết cho 2; 22 chia hết cho 2; 112 chia hết cho 2 => 390 - 22 + 122 chia hết cho 2

A. chia hết cho 2

B. không chia hết cho 2

C. chia hết cho 2

D.chia hết cho 2

Học tốt nhé

A) 132 + 50

Ta có : \(132⋮2\) ; \(50⋮2\)

\(\Rightarrow132+50⋮2\)

\(A)-\dfrac{7}{18}\) và \(-\dfrac{5}{12}\)

\(+)-\dfrac{7}{18}=-\dfrac{14}{36};-\dfrac{5}{12}=-\dfrac{15}{36}\)

\(+)14< 15\Rightarrow-\dfrac{14}{36}>-\dfrac{15}{36}\Rightarrow-\dfrac{7}{18}>-\dfrac{5}{15}\)

Vậy \(-\dfrac{7}{18}>-\dfrac{5}{12}\)

\(B)\dfrac{123}{-124}\) và \(\dfrac{-310}{311}\)

Ta có: \(1-\dfrac{123}{124}=\dfrac{1}{124}\)\(;1-\dfrac{310}{311}=\dfrac{1}{311}\)

Có: \(\dfrac{1}{124}>\dfrac{1}{311}\Leftrightarrow1-\dfrac{123}{124}>1-\dfrac{310}{311}\)\(\Leftrightarrow1+\left(-\dfrac{123}{124}\right)>1+\left(-\dfrac{310}{311}\right)\Leftrightarrow-\dfrac{123}{124}>-\dfrac{310}{311}\)

Hay \(\dfrac{123}{-124}>\dfrac{-310}{311}\)

Vậy \(\dfrac{123}{-124}>\dfrac{-310}{311}\)

d

tick nha

D

\(4^3\cdot4^{x-1}=64\)

\(\Leftrightarrow4^{x-1}=1\)

\(\Leftrightarrow x-1=0\)

hay x=1

3 11 × 2 = 6 11 6 11 : 3 11 = 6 11 × 11 3 = 66 33 = 2 6 11 : 2 = 3 11 2 × 3 11 = 6 11

\(A=1+3+3^2+...+3^{11}\)

\(=\left(1+3\right)+\left(3^2+3^3\right)+...+\left(3^{10}+3^{11}\right)\)

\(=\left(1+3\right)+3^2\left(1+3\right)+...+3^{10}\left(1+3\right)\)

\(=4\left(1+3^2+...+3^{10}\right)⋮4\)

`#3107.101107`

`A = 1 + 3 + 3^2 + ... + 3^11`

`= (1 + 3) + (3^2 + 3^3) + ... + (3^10 + 3^11)`

`= (1 + 3) + 3^2(1 + 3) + ... + 3^10(1 + 3)`

`= (1 + 3)(1 + 3^2 + ... + 3^10)`

`= 4(1 + 3^2 + ... + 3^10)`

Vì `4(1 + 3^2 + ... + 3^10) \vdots 4`

`=> A \vdots 4.`

289 x 57 + 311 x 45 + 289 x 43 + 311 x 55

= 289 x ( 57 + 43 ) + 311 x ( 45 + 55 )

= 289 x 100 + 311 x 100

= ( 289 + 311 ) x 100

= 600 x 100

= 60000 

\(289x57+311x45+289x43+311x55\)\(=289x\left(57+43\right)+311x\left(45+55\right)\)

\(=289x100+311x100=100x\left(289+311\right)\)\(=100x600=60000\)