We assume a truck as a $1\times\left(k 1\right)$ tile. Our parking is a $\left(2k 1\right)\times\left(2k 1\right)$ table and there are $t$ trucks parked in it. Some trucks are parked horizontall...

LS

Lê Song Phương

9 tháng 8 2022 - olm

We assume a truck as a $1\times\left(k+1\right)$ tile. Our parking is a $\left(2k+1\right)\times\left(2k+1\right)$ table and there are $t$ trucks parked in it. Some trucks are parked horizontally and some trucks are parked vertically in the parking. The vertical trucks can only move vertically (in their column) and the horizontal trucks can only move horizontally (in their row). Another truck is willing to enter the parking lot (it can only enter form somewhere on the boundary). 1....

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#Toán lớp 10

0

TH

Trần Hoàng Phương Anh

17 tháng 7 2017 - olm

$CMR:a^{2k+1}+b^{2k+1}⋮a+b\left(k\in N;a,b\in N\cdot\right)$

#Toán lớp 7

1

NT

Nguyễn Thiều Công Thành

17 tháng 7 2017

a^2k+1+b^2k+1=(a+b)(a^2k-a^2k-1b+2^2k-2.b²-...+a²b^2k-2-ab^2k-1+b^2k) chia hết cho a+b

=>đpcm

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TN

Thị Nga Trần

25 tháng 7 2018

Mai lives in a small house in the countryside . There is a long river behind the house. There is a small yard in front of the house. To the left of the house , there is a big garden .There are tall trees in the garden . To the right of the house there is a well . There are some flowers between the house and the well 1. It Mai's house small or big ? 2. Does Lan live in the city ? 3. What is behind Mai's house ? 4. Is there a garden to the right of the house ? 5. Where are the tall trees...

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#Tiếng anh lớp 6

2

TM

Trà My

8 tháng 8 2018

Mai lives in a small house in the countryside . There is a long river behind the house. There is a small yard in front of the house. To the left of the house , there is a big garden .There are tall trees in the garden . To the right of the house there is a well . There are some flowers between the house and the well

1. It Mai's house small or big ?It's small

2. Does Lan live in the city ?No,she doesn't

3. What is behind Mai's house ?There is a long river behind the house.

4. Is there a garden to the right of the house ?No,there isn't

5. Where are the tall trees ?There are tall trees in the garden

6. What is to the right of the house ?To the right of the house there is a well

7. Are there some flowers to the left of the house ?No,there aren't

8. Where are flowers ?There are some flowers between the house and the well

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TH

Thái Hưng

8 tháng 8 2018

Mai lives in a small house in the countryside . There is a long river behind the house. There is a small yard in front of the house. To the left of the house , there is a big garden .There are tall trees in the garden . To the right of the house there is a well . There are some flowers between the house and the well

1. It Mai's house small or big ? It is small.

2. Does Lan live in the city ? No, she doesn't.

3. What is behind Mai's house ? There is a long river behind her house.

4. Is there a garden to the right of the house ? No, there isn't.

5. Where are the tall trees ? The tall trees are in the garden.

6. What is to the right of the house ? To the right of the house there is a well

7. Are there some flowers to the left of the house ? No, there aren't

8. Where are flowers ?

There are some flowers between the house and the well

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T

Trang05

18 tháng 2 2021

1.The tank ………. . The crew is just getting out. A is parking B have parked C parks D has parked 2.Sports and other related forms of ……….. are usually for men. A entertain B entertainer C entertainment D entertaining 3.His clothes are still too wet; Sam ………. have been standing in the rain for too long. A mustn’t B can C can’t D must 4.………. you ………. the red sports car parked by the shop? A Have/seen B Do/see C Has/seen D Did/ see 5.……. to...

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#Tiếng anh lớp 10

1

NC

Nguyễn Công Tỉnh

18 tháng 2 2021

1.The tank ………. . The crew is just getting out. A is parking B have parked C parks D has parked

2.Sports and other related forms of ……….. are usually for men.

A entertain B entertainer C entertainment D entertaining

3.His clothes are still too wet; Sam ………. have been standing in the rain for too long.

A mustn’t B can C can’t D must

4.………. you ………. the red sports car parked by the shop? A Have/seen B Do/see C Has/seen D Did/ see

5.……. to our help, my sister found a suitable job with high pay. A Contrary B Own C By D Thank

s 6.The first computer can ………. with low numbers. A calculation B calculator C calculable D calculate

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HT

huynh tan viet

15 tháng 1 2018 - olm

giải pt sau bằng các định lý : $f\left(x\right)=g\left(x\right)\Leftrightarrow\left[f\left(x\right)\right]^{2k+1}=\left[g\left(x\right)\right]^{2k+1}$$\sqrt[2k+1]{f\left(x\right)}=g\left(x\right)\Leftrightarrow f\left(x\right)=\left[g\left(x\right)\right]^{2k+1}$\(\sqrt[2k+1]{f\left(x\right)}=\sqrt[2k+1]{g\left(x\right)}\Leftrightarrow...

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#Toán lớp 9

1

HT

huynh tan viet

15 tháng 1 2018

bổ xung định lý thứ 5

f(x)>=0 hoặc g(x)>=0 và f(x)=g(x)

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N

NQN

13 tháng 12 2019 - olm

Câu hỏi: Rút gọn biểu thức A = $\frac{\left(2^4+\frac{1}{4}\right)\left(4^4+\frac{1}{4}\right)\left(6^4+\frac{1}{4}\right)....\left(\left(2k\right)^4+\frac{1}{4}\right)}{\left(1^4+\frac{1}{4}\right)\left(3^4+\frac{1}{4}\right)\left(5^4+\frac{1}{4}\right)....\left(\left(2k-1\right)^4+\frac{1}{4}\right)}$ (k thuộc N*)

#Toán lớp 8

0

MT

Mao Tử

23 tháng 1 2023

Tính $lim\dfrac{\prod\limits^n_{k=1}\left(2k-1\right)}{\prod\limits^n_{k=1}\left(2k\right)}$

#Toán lớp 11

1

NB

Ng Bảo Ngọc

23 tháng 1 2023

Bạn tham khảo cách làm nha

https://diendantoanhoc.org/topic/106253-lim-nto-inftyprod-k1nfrac2k-12k/

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KA

Kaori Akechi

25 tháng 7 2018

Rút gọn đa thức sau: (làm chi tiết hộ mình nhé)

$\left(A+B\right)\left(A^{2k}-A^{2k-1}B+...+A^2B^{2k-2}-AB^{2k-1}+B^{2k}\right)$

#Toán lớp 8

1

MP

Mysterious Person

3 tháng 9 2018

câu này là hằng đẳng thức thôi . nhưng nếu muốn làm chi tiết thì đây nha :))

ta có : $\left(A+B\right)\left(A^{2K}-A^{2k-1}B+...+A^2.B^{2k-2}-AB^{2k-1}+B^{2k}\right)$

$=\left(A+B\right)\left(A^{2K}+B^{2k}-A^{2k-1}B+...+A^2.B^{2k-2}-AB^{2k-1}\right)$

$=A\left(A^{2k}+B^{2k}\right)+B\left(A^{2k}+B^{2k}\right)+A\left(-A^{2k-1}B+...+A^2B^{2k-2}-AB^{2k-1}\right)+B\left(A^{2k-1}B+...+A^2B^{2k-2}-AB^{2k-1}\right)$

$=A\left(A^{2k}+B^{2k}\right)+B\left(A^{2k}+B^{2k}\right)-A^{2k}B-B^{2k}A$

$=A^{2k+1}+AB^{2K}+BA^{2k}+B^{2k+1}-A^{2k}B-B^{2k}A$

$=A^{2k+1}+B^{2k+1}$

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KA

Kaori Akechi

3 tháng 9 2018

Cảm ơn bân nhiều =))

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KA

Kaori Akechi

25 tháng 7 2018

Rút gọn đa thức sau: (làm chi tiết hộ mình nhé)

$\left(A-B\right)\left(A^{2k-1}+A^{2k-2}B+...+AB^{2k-2}+B^{2k-1}\right)$

#Toán lớp 8

1

NL

Nguyễn Lê Phước Thịnh

30 tháng 8 2022

$=A^{2k}+A^{2k-1}B+...+A^2B^{2k-1}+AB^{2k-1}-A^{2k-1}\cdot B-A^{2k-2}\cdot B^2-...-B^{2k}$

$=A^{2k}-B^{2k}$

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BB

Bang Bang

24 tháng 7 2023

? There is a bookshelf to the left of my desk and there is a bed on the right => My desh ................ the bookshelf and the bed ? There are 6 rooms in our neu apartment => Our new apartment..............

#Tiếng anh lớp 6

1

GL

Gia Linh

24 tháng 7 2023

between

Our new apartment has 6 rooms

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QT

Quoc Tran Anh Le

Giáo viên

21 tháng 9 2023

Tính các giá trị lượng giác (nếu có) có mỗi góc sau:

a) $\frac{\pi }{3} + k2\pi \,\,\left( {k \in Z} \right)$

b) $\frac{\pi }{3}+\left( 2k+1 \right)\pi \,\,\left( k\in \mathbb{Z} \right)$

c) $k\pi \,\,\left( {k \in Z} \right)$

d) $\frac{\pi }{2} + k\pi \,\,(k \in Z)$

#Toán lớp 11

1

HQ

Hà Quang Minh

Giáo viên

21 tháng 9 2023

a)

$\begin{array}{l}\cos \left( {\frac{\pi }{3} + k2\pi \,} \right) = \cos \left( {\frac{\pi }{3}} \right) = \frac{1}{2}\\\sin \left( {\frac{\pi }{3} + k2\pi \,} \right) = \sin \left( {\frac{\pi }{3}} \right) = \frac{{\sqrt 3 }}{2}\\\tan \left( {\frac{\pi }{3} + k2\pi \,} \right) = \frac{{\sin \left( {\frac{\pi }{3} + k2\pi \,\,} \right)}}{{\cos \left( {\frac{\pi }{3} + k2\pi \,\,} \right)}} = \sqrt 3 \\\cot \left( {\frac{\pi }{3} + k2\pi \,\,} \right) = \frac{1}{{\tan \left( {\frac{\pi }{3} + k2\pi \,\,} \right)}} = \frac{{\sqrt 3 }}{3}\end{array}$

b) Các giá trị lượng giác của góc lượng giác $\frac{\pi }{3}+\left( 2k+1 \right)\pi \,\,\left( k\in \mathbb{Z} \right)$

$ \cos \left[\frac{\pi}{3}+(2 \mathrm{k}+1) \pi\right]=\cos \left(\frac{\pi}{3}+\pi+2 \mathrm{k} \pi\right)=\cos \left(\frac{\pi}{3}+\pi\right)=-\cos \frac{\pi}{3}=-\frac{1}{2}$

$\sin \left[\frac{\pi}{3}+(2 \mathrm{k}+1) \pi\right]=\sin \left(\frac{\pi}{3}+\pi+2 \mathrm{k} \pi\right)=\sin \left(\frac{\pi}{3}+\pi\right)=-\sin \frac{\pi}{3}=-\frac{\sqrt{3}}{2}$

$\tan \left[\frac{\pi}{3}+(2 \mathrm{k}+1) \pi\right]=\tan \frac{\pi}{3}=\sqrt{3}$;

$\tan \left[\frac{\pi}{3}+(2 \mathrm{k}+1) \pi\right]=\cot \frac{\pi}{3}=\frac{\sqrt{3}}{3}$

c)

$\begin{array}{l}\cos \left( {k\pi \,} \right) = \left[ \begin{array}{l} - 1\,\,\,\,\,\,\,\,\,\,\,\,\,;k = 2n + 1\\1\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,;k = 2n\,\,\,\end{array} \right.\\\sin \left( {k\pi \,} \right) = 0\\\tan \left( {k\pi \,} \right) = \frac{{\sin \left( {k\pi \,\,} \right)}}{{\cos \left( {k\pi \,\,} \right)}} = 0\\\cot \left( {k\pi \,\,} \right)\end{array}$

d)

$\begin{array}{l}\cos \left( {\frac{\pi }{2} + k\pi \,} \right) = 0\\\sin \left( {\frac{\pi }{2} + k\pi \,} \right) = \left[ \begin{array}{l}\sin \left( { - \frac{\pi }{2}} \right)\, = - 1\,\,\,\,\,\,\,;k = 2n + 1\\\sin \left( {\frac{\pi }{2}\,} \right)\, = 1\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,;k = 2n\,\,\,\end{array} \right.\\\tan \left( {\frac{\pi }{2} + k\pi \,} \right)\\\cot \left( {\frac{\pi }{2} + k\pi \,\,} \right) = 0\end{array}$

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