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对所有实数x、y,若函数y=f(x)满足f(xy)=f(x)f(y),且f(0)≠0,则f(2009)=()A.2008B.2009C.1D.2

题目详情
对所有实数x、y,若函数y=f(x)满足f(xy)=f(x)f(y),且f(0)≠0,则f(2009)=(  )
A. 2008
B. 2009
C. 1
D. 2
▼优质解答
答案和解析
因为f(xy)=f(x)f(y),
故f(0)=f(0)f(0);
又∵f(0)≠0,
∴f(0)=1,
∴f(0)=f(2009×0)=f(2009)f(0)=f(2009)=1,
故本题选C.