Hello,I'm Bill. I like swimming.This is my father.He likes reading.This is my mother.She likes singing.This is my brother.He likes skating.This is my sister.She likes dancing.What about you?
下列有关“安全操作”的叙述中正确的是( )
例:求x3﹣3x,x∈0,+∞)的最小值.解:利用基本不等式a+b+c≥3 abc3 ,得到x3+1+1≥3x,于是x3﹣3x=x3+1+1﹣3x﹣2≥3x﹣3x﹣2=﹣2,当且仅当x=1时,取到最小值﹣2
配平8Al+3Fe3O4XFe+4Al2O3反应式时,Fe前面的系数X应是( )