Nữa chu vi là

100:2=50 (cm)

CHiều dài là

50 : ( 2+3) x 3 = 30 (cm)

Chiều rộng là

50-30 = 20 (cm)

Diện tích hình chữ nhật là

20x30= 600 (cm2)

Nữa chu vi 100 : 2 = 50cm

Chiều dài 50 : ( 2 + 3) . 3 = 30cm

Chiều rộng 50 - 30 = 20cm

Diện tích hình chữ nhật 20 . 30 = 600 cm2

Chu vi: 100 cm

Chiều rộng : :--:

Chiều dài: :---:

of=>x 

however=>although

despite=>in spite

that=>x

for=>to

even=>x

to=>x

work=>working

will=>x

though=>but

studies=>study

although=>despite

are to be found=>are found

writting=>written

bài ở đâu vậy bạn

em lớp 4:))))

13 built this hotel for a year

14 played volleyball for a year

15 listened to music since 4 p.m

16 been there since last month

17 have you lived here

18 have you known her

19 did you wrote this book

20 working in this factory when he was 18

VI

1 is the first time I have met him

2 the first time I have eaten this kind of food

3 is the first time I have seen this film

4 the first time we have drunk this kind of water

5 the first time he has been to HCM city

6 never seen this man before

7 never phoned me before

8 never talked to her before

9 never used computer before

10 never sung before

11 the first time Ba hass listened to classical music

\(2x^2-5x^2+3x=0\)

\(\Leftrightarrow-3x^2+3x=0\)

\(\Leftrightarrow-3x\left(x-1\right)=0\)

\(\Leftrightarrow\left[{}\begin{matrix}-3x=0\\x-1=0\end{matrix}\right.\)

\(\Leftrightarrow\left[{}\begin{matrix}x=0\\x=1\end{matrix}\right.\)

Vậy \(S=\left\{0;1\right\}\)

Áp dụng định luật ll Niu tơn:

\(m\cdot\overrightarrow{a}=\overrightarrow{F}\) hay \(\dfrac{\overrightarrow{v_2}-\overrightarrow{v_1}}{\Delta t}=\overrightarrow{F}\)

\(\Rightarrow\Delta t=\dfrac{v_2-v_1}{F}=\dfrac{15-10}{10}=0,5s\)

Xung lượng của lực:

\(m\cdot\overrightarrow{v_2}-m\cdot\overrightarrow{v_1}=\overrightarrow{F}\cdot\Delta t\)

Mà \(\Delta\overrightarrow{p}=m\overrightarrow{v_2}-m\overrightarrow{v_1}\)

\(\Rightarrow\Delta\overrightarrow{p}=\overrightarrow{F}\cdot\Delta t\)

Vậy xung lượng lực trong khoảng thời gian \(\Delta t\) là:

\(\Delta p=F\cdot\Delta t=10\cdot0,5=5kg.\)m/s

mk ko bt

2^2.3^1-(1^2021+2021^2) : (-2)

= 4.3-(1+4084441 ) : (-2)

= 12-4084442:(-2)

= 12-(-2042221)

= 20421133