问题
填空题
已知已知函数f（x）=x3+3，若f（lga）=4，则f（lg
|
答案
∵lg
=-lga，而f（x）+f（-x）=x3+3+（-x）3+3=6，1 a
∴4+f(lg
)=6，∴f(lg1 4
)=2．1 4
故答案为2．
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已知已知函数f（x）=x3+3，若f（lga）=4，则f（lg
|
∵lg
=-lga，而f（x）+f（-x）=x3+3+（-x）3+3=6，1 a
∴4+f(lg
)=6，∴f(lg1 4
)=2．1 4
故答案为2．
| 完型填空 | |||||
| It was a beautiful day. The weather was perfect for a picnic, so when lunch time came, we set our sights on a small 1 in town. We decided to 2 up by the pond near the entrance. Then my friend Robby 3 for a hot dog stand (摊), and I decided to keep her company (陪伴). We 4 the man put together the perfect hot dog just the way Robby wanted it. 5 when she took out her money to pay him, the man 6 us. He said, "This is my freebie (免费赠品) of the day." We thanked him and 7 our friends in the park. On our way back, I was 8 by a man sitting alone nearby, 9 at us. I could tell by his appearance that he hadn't 10 for days. Another homeless person, I thought. But when Robby and I went to the garbage can to 11 away our lunch bag, I heard a 12 voice ask, "There isn't any 13 in the bag, is there?" It was the man who had been watching us. "No, I 14 it already." "Oh" was his only answer, with 15 in his voice. He was obviously 16 . Suddenly Robby said, "I'll be right back. Please wait for a minute," and ran off. I watched with 17 as she went across to the hot dog stand. Then I 18 what she was doing. She bought a hot dog and gave it to the man. "I was just passing on the 19 that someone gave to me," Robby said. That day I learned how generosity can go 20 than the person you give to. By giving, you also teach others how to give. | |||||
| ( )1. A. park ( )2. A. show ( )3. A. sought ( )4. A. watched ( )5. A. So ( )6. A. frightened ( )7. A. reminded ( )8. A. attracted ( )9. A. waving ( )10. A. drunk ( )11. A. throw ( )12. A. serious ( )13. A. trash ( )14. A. sold ( )15. A. doubt ( )16. A. hungry ( )17. A. admiration ( )18. A. recognized ( )19. A. kindness ( )20. A. wider | B. yard B. meet B. searched B. helped B. And B. amused B. invited B. pulled B. staring B. worked B. put B. low B. paper B. fell B. shame B. angry B. curiosity B. believed B. friendship B. further | C. garden C. dress C. looked C. ordered C. But C. surprised C. called C. attacked C. laughing C. exercised C. get C. sweet C. food C. ate C. pleasure C. calm C. excitement C. imagined C. peace C. deeper | D. beach D. pick D. headed D. made D. Thus D. interested D. joined D. injured D. smiling D. showered D. take D. strong D. bottles D. bought D. disappointment D. nervous D. concern D. realized D. respect D. higher | ||