(Ⅰ)求函数f(x)的定义域;
(Ⅱ)若g(x)=f( 1+x2x2 ),(x≠0),求g(x)的解析式和最小值.
{x−1≠0x−1>0<
公比为4的等比数列{bn}中,若Tn是数列{bn}的前项积,则有T20T10,T30T20,T40T30也成等比数列,且公比为4100;类比上述结论,相应的在公差为3的等差数列{an}中,若Sn是{an}的前n项和,则有一相应的等差数列,该等差数列的公差为( )
Mike is a middle school student. He goes to school from Monday to Friday. His home is about 5 miles from school. He usually walks to school. It takes him 30 minutes to walk there. Nancy's home is a little farther. It's 20 miles from school. So she often takes the school bus. It takes her 15 minutes to get to school. Bob lives outside the city. It's a town 30 miles away from his school. He takes the subway. It takes him 8 minutes to get to school by subway. He can have breakfast at home and then leave for the subway station. He studies very hard.
“人之有所不为,皆赖有耻之心,若无耻心,则无事不可为矣”。这句话告诉我们 ( )
下列数中是无理数的是( )。