= \(\frac{1996\times\left(1994+1\right)-996}{1000+1996\times1994}=\frac{1996\times1994+1996-996}{1000+1996\times1994}\)

= \(\frac{1996\times1994+1000}{1000+1996\times1994}\)

= 1

\(S1=2^1+2^2+2^3+....+2^{50}\)

\(2S1=2^2+2^3+2^4+...+2^{51}\)

\(2S1-S1=\left(2^2+2^3+2^4+...+2^{51}\right)-\left(2^1+2^2+2^3+....+2^{50}\right)\) 

\(S1=2^{51}-2\)

Số gà trống là :

10350*1/5=2070 [con]

Đ/S: 2070 con

1. What is your surname?

2. Where do you live?

3. Who do you live with?

4. How do you go to school?

5. What time do you go to school?

6. Why are you late for school?

7. How many close friends do you have?

Hơ hơ, cái j đây

a) My father has less days off than Tim's father

                      A        B              C     D

=> Câu này k có lỗi, lỗi ở bạn đưa đề sai

b) Milion of foreign visitors come to Vietnam every year on their holiday

         A              B                            C                             D

A. Million  => Millions

c) My sister likes badminton but she doesn't play it very good

                         A                            B                C                D        D. Very good => Very well

Ta có: \(\frac{x-1}{2}=\frac{2x-2}{4};\frac{y-2}{3}=\frac{3y-6}{9}\) 

=> \(\frac{2x-2}{4}=\frac{3y-6}{9}=\frac{z-3}{4}\) và \(2x+3y-z=50\)

Áp dụng tính chất của dãy tỉ số bằng nhau, ta có:

\(\frac{2x-2}{4}=\frac{3y-6}{9}=\frac{z-3}{4}=\frac{2x-2+3y-6-z+3}{4+9-4}\)

\(=\frac{2x+3y-z-\left(2+6-3\right)}{9}=\frac{50-5}{9}=5\)

=> \(x=5.2+1=11\)

\(y=5.3+2=17\)

\(z=5.4+3=23\)

Sao dài dữ zỏ???Giải hết có mak đến sáng mai??!!!@   ~_~

1. My uncle (move) moved to Da Lat in 2005.

2. The Greens (live) have lived in this city for 10 years.

3. My father (work) has worked for the foreign company since last year.

4. We (spend) spent our summer vacation in Ha Long Bay last July.

5. Our teacher (explain) has explained to us how to use the printer already.

6. The postman (deliver) delivered the letter half an house ago.

7. Mai (not finish) hasn't finished her homework yet.

8. I (visit) have visited our form teacher in the hospital already.

9. I (hear) heard/have heard the good news from Mary a few minutes ago.

10. They (not start) haven't started the project yet.