问题 填空题
若f(x+y)=f(x)•f(y),且f(1)=1,则
f(2)
f(1)
+
f(4)
f(3)
+…+
f(2010)
f(2009)
+
f(2012)
f(2011)
=______.
答案

∵f(x+y)=f(x)•f(y),f(1)=1,

令y=1,则f(x+1)=f(x)•f(1),

f(x+1)
f(x)
=f(1)=1,

f(2)
f(1)
+
f(4)
f(3)
+…+
f(2010)
f(2009)
+
f(2012)
f(2011)
=1006

故答案为:1006

单项选择题
名词解释