求值：sin(－1 200°)·cos 1 290°＋cos(－1 020°)·sin(－1 050°)＋tan 945°.
2
解：原式＝－sin 1 200°·cos 1 290°＋cos 1 020°·(－sin 1 050°)＋tan 945°＝－sin 120°·cos 210°＋cos 300°·(－sin 330°)＋tan 225°＝(－sin 60°)·(－cos 30°)＋cos 60°·sin 30°＋tan 45°＝
×＋
×＋1＝2.
Passage Three
What mistaken view do most people hold about Arabic
A．Colloquial Arabic is the everyday spoken language, which varies from country to country.
B．Arabic is just one language that all Arabs understand, speak and write.
C．Classical Arabic and Modem Arabic are two different kinds of written Arabic.
D．Pan-Arabic provides a means of communication between educated people of different Arab nationalities.
