Chứng minh: a²+a+1/ a²-a+1 >0

Read the passage below and decide whether the statements are TRUE or FALSE?

Bowing is nothing less than an art form in Japan, respect pounded into children’s heads from the moment they enter school. For tourists, a simple inclination of the head or an attempt at a bow at the waist will usually suffice. The duration and inclination of the bow is proportionate to the elevation of the person you’re addressing. For example, a friend might get a lightning-fast 30-degree bow; an office superior might get a slow, extended, 70-degree bow. It’s all about position and circumstance.

There is no tipping in any situation in Japan — cabs, restaurants, personal care. To tip someone is actually a little insulting; the services you’ve asked for are covered by the price given, so why pay more? If you are in a large area like Tokyo and can’t speak any Japanese, a waiter or waitress might take the extra money you happen to leave rather than force themselves to deal with the awkward situation of explaining the concept of no tipping in broken English.

Question: A lightning-fast 30-degree bow is used for friends.

A. True

B. False

Choose the letter A, B, C or D to complete the sentences

Japan suffers from a large number of __________ every year.

A. typhoons

B. workers

C. eruption

D. earthquakes