b) CMR 1/4^2+1/6^2+1/8^2+...+1/(2n)^2<1/4 bài2 cho A=10^2012+10^2011+10^2010+10^2009+8 a)CMR A chia hết cho 24 b) CMR A ko phải là số chính phương alo linh

Các câu hỏi liên quan

Joining two sentences, using the words in brackets. 1. We must conserve water. Otherwise we will face serious water shortages. (IF) ____________________________________________________________________ 2. The weather was awful. We didn’t enjoy our camping holiday. (BECAUSE OF) ____________________________________________________________________ 3. Plastic bags are non-biodegradable. They will remain in the environment for many years. (SINCE) ____________________________________________________________________ 4. Paul doesn’t think about the planet. He wastes so much water. (IF) ____________________________________________________________________ 5. Water pollution happens. Many aquatic animals such as fish can die. (LEAD) ____________________________________________________________________ 6. The climate is changing. The earth is getting warmer. (BECAUSE) ____________________________________________________________________ 7. We should stop cutting down so many trees. We endanger our oxygen supply. (UNLESS) ____________________________________________________________________ 8. People begin to recycle. They generate much less trash. (WHEN) ____________________________________________________________________ 9. We are damaging the ozone layer. The ozone layer is necessary for human existence. (EVEN THOUGH) ____________________________________________________________________ 10. Sue is suffering from skin cancer. She was exposed to radiation when she was young. (SO) ____________________________________________________________________