Cho \(a\ne b\ne c\) và \(\dfrac{1}{a}+\dfrac{1}{b}+\dfrac{1}{c}=0\), tính \(P=\dfrac{1}{a^2-2bc}+\dfrac{1}{b^2+2ac}+\dfrac{1}{c^2+2ab}\).

Tìm \(A_{min}=a^4-2a^3-4a+5\)

 \(A=3^0-3^1+3^2-...-3^9+3^{10}\)

1, B (1-2-1-1)

2, D (1-1-1-2)

1. Mom, dad,  may I have a party?

2. Alice, can you help me with my homework?

3. Excuse me, could you tell me where the changing rooms are?

4. Jane, can I borrow your phone to make a call?

5. May I leave school early?

6. Dad, could you mend my bike?

*It's quite easy for me :)*