Prove that the following equation has no positive integer solution :

\(4xyz-x-y=t^2\)   

For a ; b ; c is a non-negative real number: a + b + c = 3. Prove that : \(\left(3abc+1\right)\left(a^2b+b^2c+c^2a\right)\ge12abc\)

Đơn vị đo độ dài nào lớn nhất trong các đo độ dài sau?

a.Pasếc           b.Năm ánh sáng

c.Km               d.Đơn vị thiên văn

Đố vui:

Vừa bằng hạt đỗ, ăn giỗ cả làng

Là con gì?

các bạn giúp mik nha

I. Rewrite the sentences below so that it has a similar meaning to the first, beginning with the words given

1. I find his handwriting very hard to read

-> I have....................

2. He got down to writing a letter as soon as he returned from his work

-> No sooner.................................

3. "If I were you, I wouldn't accept his marriage proposal", said Nam to Lan

-> Nam................

4. No matter how hard I tried, I could not open the window

-> Try.......................

5. Please don't ask me that question

-> I'd rather.............

II. Finish the second sentence so that it has the same meaning as the first one, using the given words. Do not change the given word

1. The fridge is complete empty (LEFT)

-> 

2. It is pointless to have that old typewriter repaired (WORTH)

->

3. Frank never pays any attention to my advice. (NOTICE)

-> 

4. John only understood very little of what the teacher said (HARDLY_

->

5. Her ability to run a company really impresses me (IMPRESSED)

->

Let \(x\in R.\) Prove that

                \(\sqrt{6+4\sqrt{2}\sin x}+\sqrt{3-2\sqrt{2}\cos x}\le2+\sqrt{2}\)