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Câu hỏi của Ngô Ngọc Anh - Toán lớp 9 - Học toán với OnlineMath

1 if he will páy me tonight, i wil..........

2 if i ................................................

3 unless they invite me, i won't come

4 bỏ dấu phảy, đổi hai vế cho nhau

1. He will pay me tonight; I will have enough money to buy a car.

> If .....he pays me tonight, I will have enough money to buy a car.........................

2. I will get a work permit. I will stay for another month.

> If ........I get a work permit. I will stay for another month...................

3. I only come if they invite me.

> Unless ....they invite me, I won't come.....................

4. If I arrive at the office earlier than I do, please turn on the air-conditioner.

> Should  I arrive at the office earlier than I do, please turn on the air-conditioner...............................

5. He died so young; otherwise, he would be a famous musician by now.

> Had ..he not died so young, he would be a famous musician by now..........................

6. The car breaks down so often because you don't take good care of it.

> Were I to take good care of the car, it wouldn't break down so often ................................

7. She got married at such an early age; otherwise, she would be at university now.

> Had .she not got married at such an early age, she would be at university now. ...............................

\(\text{BĐT}\Leftrightarrow x^4+y^4+z^4\ge xyz\left(x+y+z\right)\) (để ý giả thiết để đồng bậc 2 vế)

Giả sử \(z=min\left\{x,y,z\right\}\)

Ơ quên điều kiện x, y, z là các số thực -_-

\(B\text{Đ}T\Leftrightarrow x^4+y^4+z^4\ge xyz\left(x+y+z\right)\)

\(VT-VP=\frac{1}{2}\left[\Sigma_{cyc}\left(x^2-y^2\right)^2+\Sigma_{cyc}\left(xy-yz\right)^2\right]\ge0\)

8/3xa/b=10-6

8/3xa/b=4

a/b=8/3:4

a/b=2/3

a x 20 - a = 19 x20 -19

a x { 20 -1} = 19 x [ 20 - 1}

a x19 = 19 x19

a = 19x19 :19

a=19

vậy a = 19

a * 20 - a =19 * 20 +19

     19 * a = 19*21

=>        a = 21

Vậy a = 21

(x+1)+(x+5)+(x+9)+...+(x+45)=331,2

=> x nhân12 + 276=331,2

=>x nhân 12=331,2-276

=>x nhân 12=55,2

=> x= 4,6

học tốt nhé

Ta có : (x + 1) + (x + 5) + (x + 9) + .... + (x + 45) = 331,2 (12 cặp )

=> (x + x + ... + x) + (1 + 5 + 9 + ... + 45) = 331,2

    12 số hạng x          12 số hạng

=> \(12\times x+12\times\left(45+1\right):2=331,2\)

=> \(12\times x+276=331,2\)

=> \(12\times x=55,2\Rightarrow x=4,6\)

Vậy x = 4,6

chưa đâu nek

t i c k nha baybe

ok baby

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