问题
选择题
函数f（x）=sin2x+asin（
|
答案
∵f（x）=sin2x+asin（
-2x）的图象关于直线x=-π 2
对称，π 8
∴f（0）=f（-
），即0+asin（π 4
-0）=sin（-π 2
）+asin（π 2
-（-π 2
）），π 2
∴0+a=-1+0，
∴a=-1．
故选C．
搜题请搜索小程序“爱下问搜题”
函数f（x）=sin2x+asin（
|
∵f（x）=sin2x+asin（
-2x）的图象关于直线x=-π 2
对称，π 8
∴f（0）=f（-
），即0+asin（π 4
-0）=sin（-π 2
）+asin（π 2
-（-π 2
）），π 2
∴0+a=-1+0，
∴a=-1．
故选C．
| 完形填空。 | |||
| Jimmy began painting when he was three years old. When he was five, he was already very good at it. He painted 1 beautiful pictures and a lot of people 2 his pictures. They said, "This boy is going to be famous when he is a little older,and then we are going to sell these pictures 3 a lot more money." Jimmy’s pictures were 4 other people’s, because he never painted on all the paper. He painted on half of it, and the other half was always 5 . "That’s very clever,” everybody said. " 6 other painters did that before!" One day somebody bought one of Jimmy’s pictures and said to him, “Please tell me this, Jimmy. 7 do you paint on the bottom half of your pictures, 8 not on the top half?" "Because I’m 9 , " Jimmy said, " and my brushes don’t 10 very high." | |||
| ( )1. A. many ( )2. A. found ( )3. A. with ( )4. A. different from ( )5. A. nice ( )6. A. Some ( )7. A. What ( )8. A. then ( )9. A. small ( )10. A. paint | B. few B. bought B. to B. cheaper than B. blue B. A few B. Why B. or B. young B. reach | C. a few C. looked at C. from C. hard to C. empty C. Many C. Which C. so C. busy C. clean | D. some D. took away D. for D. popular with D. free D. No D. When D. but D. strong D. write |