1 f(x)Max=f(2)=1/3 f(x)min=f(3)=1/4
2 f(x)Max=f(2)=1/a-1/2=2 所以 a=2/5
3 f(正负根号下3)=-1 f(正负根号下5)=3 b-a=根号下5-根号下3
4 负无穷到-1 单调递减
1到正无穷单调递增
1 f(x)Max=f(2)=1/3 f(x)min=f(3)=1/4
2 f(x)Max=f(2)=1/a-1/2=2 所以 a=2/5
3 f(正负根号下3)=-1 f(正负根号下5)=3 b-a=根号下5-根号下3
4 负无穷到-1 单调递减
1到正无穷单调递增