3.下列计算中,错误的是( )
| A. | 5a3-a3=4a3 | B. | 2n•3n=6n+n | C. | (a-b)3•(b-a)2=(a-b)5 | D. | -a2•(-a)3=a5 |
1.在-4,2,-1,3,-2这五个数中,最小的数是( )
| A. | -4 | B. | 2 | C. | -1 | D. | 3 |
17.下列计算正确的是( )
0 284655 284663 284669 284673 284679 284681 284685 284691 284693 284699 284705 284709 284711 284715 284721 284723 284729 284733 284735 284739 284741 284745 284747 284749 284750 284751 284753 284754 284755 284757 284759 284763 284765 284769 284771 284775 284781 284783 284789 284793 284795 284799 284805 284811 284813 284819 284823 284825 284831 284835 284841 284849 366461
| A. | 3+2$\sqrt{2}$=5$\sqrt{2}$ | B. | $\sqrt{2}$+$\sqrt{5}$=$\sqrt{5}$ | C. | 2$\sqrt{\frac{1}{2}}$=2 | D. | 4$\sqrt{3}$-3$\sqrt{3}$=$\sqrt{3}$ |