Chứng minh đẳng thức

\(\left(a+b\right)^2-\left(a-b\right)\left(a+b\right)=2b\left(a+b\right)\)

Chứng minh \(n\left(3-2n\right)-\left(n-1\right)\left(1+4n\right)-1\) chia hết cho 6 với mọi số nguyên \(n\)

Write a similar paragraph to answer one of the following questions (not too long).

1. What do you think is the best leisure activity for teenagers?

2. Should parents decide how teenagers spend their free time?

Giúp mình với, đừng chép mạng nhé!

Tính giá trị \(B=2\frac{1}{33}\times\frac{1}{59}-\frac{1}{11}\times3\frac{58}{59}-\frac{4}{33\times59}+\frac{4}{11}\)

Tính giá trị \(A=x^4-10x^3-9x^2-21x+5\) với \(x=11\)

Cho a, b \(\in\)N biết \(a\div4\) dư 1; \(b\div4\) dư 2. Chứng tỏ \(a.b\div4\) dư 2.

Chứng tỏ 1000001 (5 chữ số 0) là hợp số

Cho \(xy=6\) và \(x^2+y^2=37\) Tính \(x^3+y^3\)

Rewrite the sentence using the word in bracket

1. He doesn't know enough English vocabulary to talk to foreigners (wishes)

2. He played so well that he recieved a thunderous ovation from the audience (such)

➝ His .............

3. Sam tried extremely hard to convince her, but it wasn't use (bring)

➝ Hard ..............

4. Unless you take the train, you will be late for work (make)

➝ Only by ..............

5. Surprisingly, the website wouldn't allow me to access certain pages (which)

➝ The website denied ..............

6. She worked hard during her final year. There for she easily god admitted to this prestigious high school (industry)

➝ Had it ..............