已知函数f(x)=cosπx (x≤0)f(x-1)+1 (x>0),则f(4/3)+f(-4/3)= _ .
问题描述:
已知函数f(x)=
,则f(
cosπx (x≤0) f(x-1)+1 (x>0)
)+f(-4 3
)= ___ .4 3
答
f(
)=f(4 3
-1)=f(4 3
)=cos1 3
π=1 3
1 2
f(-
)=cos(-4 3
π)=cos(4 3
π)=cos(π+4 3
π)=1 3
.1 2
所以则f(
)+f(-4 3
)=4 3
+1 2
=11 2
故答案为:1