A____ great importance to this research, the professor spared no efforts to do the experiment.
下列四个数中,在﹣2到﹣1之间的数是( )
执行如图的程序框图,若输出的k=2,则输入x的取值范围是( )
已知函数f(x)=x3﹣x+2 x .
(Ⅰ)求函数y=f(x)在点(1,f(1))处的切线方程;
(Ⅱ)令g(x)= ax2+axf(x)−2x +lnx,若函数y=g(x)在(e,+∞)内有极值,求实数a的取值范围;
(Ⅲ)在(Ⅱ)的条件下,对任意t∈(1,+∞),s∈(0,1),求证: g(t)−g(s)>e+2−1e .
写作____,读作____