问题
填空题
若f(x+y)=f(x)f(y),且f(1)=2,则
|
答案
∵f(x+y)=f(x)f(y),
∴
=f(y),则f(x+y) f(x)
=f(x-y)f(x) f(y)
∴
+f(2) f(1)
+…+f(3) f(2)
=2005f(1)=4010f(2006) f(2005)
故答案为4010
若f(x+y)=f(x)f(y),且f(1)=2,则
|
∵f(x+y)=f(x)f(y),
∴
=f(y),则f(x+y) f(x)
=f(x-y)f(x) f(y)
∴
+f(2) f(1)
+…+f(3) f(2)
=2005f(1)=4010f(2006) f(2005)
故答案为4010