x^2+y^2-2xy+x_y+1 chứng minh đa thức k âm với mọi giá trị của x,y,z

31. My mother took me to the zoo yesterday

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32. Blair invented a color television in 1928.

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33. John gave me these records last week.

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34. Our club holds meetings once a month.

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35. She doesn’t find anything in that box.

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Choose the best answer.

We are looking for ____ place to spend ____ night.

Choose the best answer.

Please turn off ___ lights when you leave ___ room.

Choose the best answer.

I like _____ colorful costumes of ____ ethnic minority people in Vietnam.