viết câu hoàn chỉnh, sử dụng các từ/ cụm từ gợi ý:

1. I/ often/ go/ fish/ when/ it/ hot.

2. There/ be/ a lot/ river/ world.

3. The Nile River/ long/ river/ world.

4. My friend/ not/ live/ his family/ Ha Noi.

5. Lan/ usually/ listen/ music/ her free time.

6. My apartment/ small/ and/ it/ seventh/ floor.

7. My school/ start/ seven o'clock/ and/ finish/ eleven thirty.

8. Right now/ Hoa/ music room/ and/ she/ sing/ English song.

9. The toy store/ between/ bookstore/ bakery.

10. There/ table/ four chairs/ living room.

tìm x biết:

a, 2x-3+(-7)=x-5-12

b, 3-(5x+7)=-2x-(2x+3)

c, 2x-9-(15-27)=21-(12-x)

cho x ∈ z. so sánh -5.x với 0

cho A= \(\dfrac{x+3}{x-1}\) với x thuộc z

tìm x để A lớn nhất, nhỏ nhất

cảm ơn bảo nhiều nke

A=10(1/1.2+5/2.3+...+89/9.10)

A=10(1/2+5/6+...+89/90)

A=10[(1-1/2)+(1-1/6)+.....+(1-1/90)

A=10(1-1/2+1-1/6+...+1-1/90)

A=10[(1+1+...+1)-(1/2+1/6+...+1/90)

           9 chữ số 1

A=10[9-(1/1.2+1/2.3+...+1/9.10)]

A=10[9-(1-1/2+1/2-1/3+...+1/9-1/10)]

A=10[9-(1-1/10)]

A=10(9-9/10)

A=90-9=81