“小马虎”在下面的计算中只做对一道题,你认为他做对的题目是( )
A.(ab)2=ab2 | B.(a3)2=a6 | C.a6÷a3=a2 | D.a3•a4=a12 |
已知xm=3,xn=5,求xm+n.
(1)一变:已知xm=3,xn=5,求x2m+n;
(2)二变:已知xm=3,xn=15,求xn-m.
(1)一变:已知xm=3,xn=5,求x2m+n;
(2)二变:已知xm=3,xn=15,求xn-m.