A:13 12
B:3 13
C:15 34
D:3 14
步骤一:配制培养基:通常加入琼脂或明胶以便形成固体培养基.
步骤二:重复实验:A组实验接种正常R型细菌;B组接种正常S型菌;C组接种加热杀死的S 型菌:D组接种加热杀死的S型菌和正常的R型菌的混合液.培养结果如下.
— Would you like to go for a picnic with me?
— ______ I have to help Kate with her Chinese
已知函数f(x)=xeax+lnx﹣e,(a∈R)
(1)当a=1时,求函数y=f(x)在点(1,f(1))处的切线方程.
(2)设g(x)=lnx+1x﹣e,若函数h(x)=f(x)﹣g(x)在定义域内存在两个零点,求实数a的取值范围.