2.
如图,AB为⊙O的直径,弦CD⊥AB,E为弧BC上一点,若∠CEA=28°,则∠ABD=( )
| A. | 14° | B. | 28° | C. | 56° | D. | 80° |
19.
如图,在△ABC中,∠ACB=90°,∠A=30°,AB的垂直平分线分别交AB和AC于点D,E,AE=2,CE=( )
| A. | 1 | B. | $\sqrt{2}$ | C. | $\sqrt{3}$ | D. | $\sqrt{5}$ |
18.
如图,在平面直角坐标系xOy中,A(-2,0),B(0,2),⊙O的半径为1,点C为⊙O上一动点,过点B作BP⊥直线AC,垂足为点P,则P点纵坐标的最大值为( )
| A. | $2\sqrt{2}$ | B. | $\frac{{\sqrt{3}+1}}{2}$ | C. | 2 | D. | $\frac{3}{2}$ |
15.因式分解x2-9的结果是( )
| A. | (x+9)(x-9) | B. | (x+3)(x-3) | C. | (3+x)(3-x) | D. | (x-3)2 |
14.把x2+x+m因式分解得(x-1)(x+2),则m的值为( )
| A. | 2 | B. | 3 | C. | -2 | D. | -3 |
13.已知矩形一边的长为5,另一边的长为4,则它的对角线的长为( )
0 284187 284195 284201 284205 284211 284213 284217 284223 284225 284231 284237 284241 284243 284247 284253 284255 284261 284265 284267 284271 284273 284277 284279 284281 284282 284283 284285 284286 284287 284289 284291 284295 284297 284301 284303 284307 284313 284315 284321 284325 284327 284331 284337 284343 284345 284351 284355 284357 284363 284367 284373 284381 366461
| A. | 3 | B. | $\sqrt{41}$ | C. | 4 | D. | 2$\sqrt{41}$ |