17.下列方程中是一元一次方程的是( )
| A. | 2x-4=y+2 | B. | 5x-3=6x+1 | C. | xy=2 | D. | x+$\frac{1}{x}$=2 |
16.在数1,0,-1,-2中最小的数是( )
| A. | -1 | B. | 0 | C. | -2 | D. | 1 |
15.下列运算正确的是( )
| A. | x-2•x4=x8 | B. | 3x+2y=6xy | C. | (x-3)-2=x6 | D. | y3÷y3=y |
14.在代数式xy2中,x与y的值各减少了$\frac{1}{4}$,则该代数式的值减少了( )
| A. | $\frac{1}{2}$ | B. | $\frac{3}{4}$ | C. | $\frac{37}{64}$ | D. | $\frac{27}{64}$ |
10.若第二象限内的点P(x,y)满足|x|=3,y2=25,则点P的坐标是( )
| A. | (3,5) | B. | (3,-5 ) | C. | (-3,5) | D. | (-3,-5) |
9.实数$\root{3}{11}$,0,$-\frac{1}{2}π$,$\sqrt{9}$,-$\frac{1}{3}$,0.3131131113…(相邻两个3之间依次多一个1),其中无理数的个数是( )
| A. | 4 | B. | 2 | C. | 1 | D. | 3 |
8.25的平方根是( )
0 293342 293350 293356 293360 293366 293368 293372 293378 293380 293386 293392 293396 293398 293402 293408 293410 293416 293420 293422 293426 293428 293432 293434 293436 293437 293438 293440 293441 293442 293444 293446 293450 293452 293456 293458 293462 293468 293470 293476 293480 293482 293486 293492 293498 293500 293506 293510 293512 293518 293522 293528 293536 366461
| A. | ±5 | B. | 5 | C. | ±$\sqrt{5}$ | D. | -5 |