问题 填空题

设f(x)=(x-1)(x-2)(x-3)…(x-2010)则f′(2010)=______.

答案

∵f(x)=(x-1)(x-2)(x-3)…(x-2010),

∴f′(x)=[(x-1)(x-2)(x-3)…(x-2009)]′(x-2010)+[(x-1)(x-2)(x-3)…(x-2009)](x-2010)′

=[(x-1)(x-2)(x-3)…(x-2009)]′(x-2010)+[(x-1)(x-2)(x-3)…(x-2009)]

∴f′(2010)=2009×2008×…×1=2009!

故答案为2009!.

问答题
单项选择题 A1/A2型题