f(x)=sinx在[0,2π]上满足罗尔定理的点ξ是()。
A.仅有
B.
C.
D.
参考答案:C
解析:
ξ是在(0,2π)内,f'(x)=cosx=0的点,而。
硝基腐植酸钠具有良好的()作用。
A.降滤失和降粘
B.降滤失和提粘
C.增粘和抑制
D.降粘和堵漏
Peter is a ______ boy. He does everything . [ ]
A. carefully, careful
B. careful, carefully
C. careful, careful
D. carefully, carefully