\(1+2+3+4+5+...+300\)

\(\Rightarrow\frac{\left(300+1\right)\left[\left(300-1\right):1+1\right]}{2}=45150\)

vậy tổng trên bằng 45150

45150

Hiệu 2 số là:

13 × 2 + 2 = 38

Số bé là:

(2012 - 38) : 2 = 987

Số lớn là:

2012 - 987 = 1025

ĐS: 987 và 1025

I/ Choose the word having the underlined part pronounced differently in each line

1.          A. Chairs       B. Sofas          C. Rooms            D. Sinks

2.          A. Lamps      B. Halls           C. Desks              D. Lights

3.          A. Vases       B. Fridges       C. Dishes             D. Tables

4.          A. Houses      B. Pictures     C. Wardrobes      D. Book selves

5.         A. Bag            B. Family        C. Bath                D. Fan

II/ Read the conversation below. Underline the final s/es in the words and write /z/ or /s/

Van: Do you live town, Tom?

Tom: Yes, I live in an apartment with my parents.

Van: How many rooms are there in your apartment?

Tom: There are four rooms :a living room, a kitchen, two bedrooms and two toilets.

Van : Is there a supermarket near the apartment?

Tom : Yes, there are also two banks, three restaurants and two hotels.

Van: Are there any shops near it?

Tom: Yes, there are two bookshops, two bakeries and some small convenient shops

III/ Use the words in the box to complete the following passage. Each word is used only once.

This is Nam's room. His room is not very (1)....big......... .There are two (2)....chairs....... , a table. a bed, a wardrobe and an English - Vietnamese (5) ...........dictionary.................. on the table. The wardrobe is (8)....near............... the bed. Nam has many (9) .............clothes......... His clothes are all in the wardrobe. The bookshelf is on the (10).......wall.......... There are many books on it.

The words in the box:  [ big; bookshelf; chairs; clothes; dictionary; near; newspapers; opposite; right; wall. ]

I/ Choose the word having the underlined part pronounced differently in each line

1.          A. Chairs       B. Sofas          C. Rooms            D. Sinks

2.          A. Lamps      B. Halls           C. Desks              D. Lights

3.          A. Vases       B. Fridges       C. Dishes             D. Tables

4.          A. Houses      B. Pictures     C. Wardrobes      D. Book selves

5.         A. Bag            B. Family        C. Bath                D. Fan

II/ Read the conversation below. Underline the final s/es in the words and write /z/ or /s/

Van: Do you live town, Tom?

Tom: Yes, I live in an apartment with my parents.

Van: How many rooms are there in your apartment?

Tom: There are four rooms :a living room, a kitchen, two bedrooms and two toilets.

Van : Is there a supermarket near the apartment?

Tom : Yes, there are also two banks, three restaurants and two hotels.

Van: Are there any shops near it?

Tom: Yes, there are two bookshops, two bakeries and some small convenient shops

III/ Use the words in the box to complete the following passage. Each word is used only once.

This is Nam's room. His room is not very (1)....big......... .There are two (2)....chairs....... , a table. a bed, a wardrobe and an English - Vietnamese (5) ...........dictionary.................. on the table. The wardrobe is (8)....near............... the bed. Nam has many (9) .............clothes......... His clothes are all in the wardrobe. The bookshelf is on the (10).......wall.......... There are many books on it.

The words in the box:  [ big; bookshelf; chairs; clothes; dictionary; near; newspapers; opposite; right; wall. ]

Ta có :

\(b^2=\left(3+\sqrt{6+\sqrt{7+\sqrt{2}}}\right)\left(3-\sqrt{6+\sqrt{7+\sqrt{2}}}\right)\)

\(b^2=9-\left(6+\sqrt{7+\sqrt{2}}\right)\)

\(b^2=3-\sqrt{7+\sqrt{2}}\)

\(\Rightarrow b=\sqrt{3-\sqrt{7+\sqrt{2}}}\)

Tích ab :

\(ab=\sqrt{2+\sqrt{2}}.\sqrt{3+\sqrt{7+\sqrt{2}}}.\sqrt{3-\sqrt{7+\sqrt{2}}}\)

\(ab=\sqrt{2+\sqrt{2}}.\left(9-7-\sqrt{2}\right)\)

\(ab=\sqrt{2+\sqrt{2}}.\left(2-\sqrt{2}\right)\)

P/s : làm được thế này thui . Sai bỏ qua