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)=

cosπx    (x≤0)
f(x-1)+1  (x>0)
,则f(
4
3
)+f(-
4
3
)
= ___ .

f(

4
3
)=f(
4
3
-1)=f(
1
3
)=cos
1
3
π
=
1
2

f(-
4
3
)=cos(-
4
3
π)
=cos(
4
3
π)
=cos(π+
1
3
π)
=
1
2

所以则f(
4
3
)+f(-
4
3
)
=
1
2
+
1
2
=1

故答案为:1