In a bowl has 2020 balls. Peter and David play ball picking game, each person alternate each other to take from 1 to 2 balls . David needs to picked before or after to:

a, David takes the last ball

b, David leave for Peter the last ball.

Solve and explain for me!

Tìm các số nguyên tố p,q và m,n nguyên dương sao cho p^2m +q²ⁿ là số chính phương.

Giúp mình với! Mình cần gấp ạ!

2 người làm được 4 sản phẩm trong 50 phút.Hỏi 4 người làm được bao nhiêu sản phẩm trong 1 giờ?

Given that \dfrac{2x+y+z+t}{x}=\dfrac{x+2y+z+t}{y}=\dfrac{x+y+2z+t}{z}=\dfrac{x+y+z+2t}{t} x 2x+y+z+t ​ = y x+2y+z+t ​ = z x+y+2z+t ​ = t x+y+z+2t ​ . The negative value of \dfrac{x+y}{z+t}+\dfrac{y+z}{t+x}+\dfrac{z+t}{x+y}+\dfrac{t+x}{y+z} z+t x+y ​ + t+x y+z ​ + x+y z+t ​ + y+z t+x ​ is

Find the greatest value of prime number P in 1991P+1, so the sum is a square number! Please helpp, im strugglinggg!!!!

Các bạn giúp mik vs 

1We started launching the Green Campaign a week ago

>We have.............

2 The road is too narrow for the volume of traffic to travel

>The road is not.........

3 We are having some workers repaint the fence

>We are.................

4 People made these toys from organic material

>These toys.............

5 They may have removed all of the waste paper last week

>All of the waste paper........

6 the children used to play traditional games long ago

>Traditional games....................

Maciej carries a bookmark with this table on it to help him remember his secret four digit number. If his secret number is 8526, all he has to do is to remember the words HELP. To retrieve his number, he looks up the letters of the word HELP and finds the corresponding digits in the top row of the table. Another example: The word LOVE can be used to help Maciej remember the secret number 2525. Maciej has to remember a new secret number. Only three of the following words produce this new number. Which one does not?

Let \(x\in R.\) Prove that

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

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)

->

Prove that the following equation has no positive integer solution :

\(4xyz-x-y=t^2\)