trung tình đọc ngược

xocd loj

a: ĐKXĐ: a>=0

b:Sửa đề: \(A=\frac{a+2}{a\sqrt{a}+1}+\frac{\sqrt{a}-1}{a-\sqrt{a}+1}-\frac{1}{\sqrt{a}+1}\)

\(=\frac{a+2}{\left(\sqrt{a}+1\right)\left(a-\sqrt{a}+1\right)}+\frac{\sqrt{a}-1}{\left(\sqrt{a}+1\right)\left(a-\sqrt{a}+1\right)}-\frac{1}{\sqrt{a}+1}\)

\(=\frac{a+2+\left(\sqrt{a}-1\right)\left(\sqrt{a}+1\right)-a+\sqrt{a}-1}{\left(\sqrt{a}+1\right)\left(a-\sqrt{a}+1\right)}=\frac{\sqrt{a}+1+a-1}{\left(\sqrt{a}+1\right)\left(a-\sqrt{a}+1\right)}\)

\(=\frac{a+\sqrt{a}}{\left(\sqrt{a}+1\right)\left(a-\sqrt{a}+1\right)}=\frac{\sqrt{a}}{a-\sqrt{a}+1}\)

c: \(A-1=\frac{\sqrt{a}}{a-\sqrt{a}+1}-1=\frac{\sqrt{a}-a+\sqrt{a}-1}{a-\sqrt{a}+1}=\frac{-a+2\sqrt{a}-1}{a-\sqrt{a}+1}\)

\(=-\frac{\left(a-2\sqrt{a}+1\right)}{a-\sqrt{a}+1}=-\frac{\left(\sqrt{a}-1\right)^2}{a-\sqrt{a}+1}\le0\forall a\) thỏa mãn ĐKXĐ

=>A<=1∀a thỏa mãn ĐKXĐ

năm 1933

1933

busy

Busy

1.How many monkeys can you see?

→ I can see five monkeys.

2.What time is it?

→ It is a quarter to four.

3.How does the boy go to the zoo?

→ He goes to the zoo by bike.

4.What would the girl like to eat?

→ She would like to eat an ice cream.

5.What do the giraffes look like?

→ The giraffes are tall and have long necks with yellow bodies and brown spots.

1.28/11/2014.

2.My favorite school things is calculator and compass.

3.6 o'clock.

4.I'm play badminton with friend.

5.không biết làm ạ

Hello

ooooo

1 She gets up at eight fifteen on Sundays

2 She wants to be sailor

3 He plays the piano

4 He goes to work by underground

5 The zebra has a black-and-white striped body

Xin cám ơn!