13.
如图,在平面直角坐标系中,矩形ABCD的边平行于坐标轴,对角线BD经过坐标原点,点C在函数y=$\frac{k}{x}$(k>0,x>0)的图象上.若点A的坐标为(-3,-3),则k的值为( )
| A. | 3 | B. | 6 | C. | 9 | D. | 12 |
9.近似数1.50所表示的准确数a的范围是( )
| A. | 1.55≤a<1.65 | B. | 1.55≤a≤1.64 | C. | 1.495≤a<1.505 | D. | 1.495≤a≤1.505 |
8.正确的算式是( )
| A. | (-1)2011=-2011 | B. | 2(-3)2=36 | C. | -3÷$\frac{1}{2}$×2=-3 | D. | $\frac{1}{2}$÷(-$\frac{1}{2}$)=-1 |
7.在实数-$\sqrt{2}$,$\frac{π}{3}$,$\frac{1}{7}$,0.80108,$\sqrt{4}$,0.$\stackrel{•}{3}$$\stackrel{•}{1}$中无理数的个数为( )
| A. | 1个 | B. | 2个 | C. | 3个 | D. | 4个 |
6.下列各式由左边到右边的变形中,是分解因式的为( )
| A. | a(x+y)=ax+ay | B. | x2-4x+4=(x-4)+4 | C. | 10x2-5x=5x(2x-1) | D. | x2-16+3x=(x-4)+3x |
5.若分式$\frac{1}{x-3}$有意义,则x的取值范围是( )
0 291343 291351 291357 291361 291367 291369 291373 291379 291381 291387 291393 291397 291399 291403 291409 291411 291417 291421 291423 291427 291429 291433 291435 291437 291438 291439 291441 291442 291443 291445 291447 291451 291453 291457 291459 291463 291469 291471 291477 291481 291483 291487 291493 291499 291501 291507 291511 291513 291519 291523 291529 291537 366461
| A. | A、x≠3 | B. | x≥3 | C. | x>3 | D. | x<3 |