已知函数f（x）=sinπ/ 2x,则f（1）+。。+f（2012)+f(2013)

当x=4kπ+1时，π/2x=2kπ+π/2 sinπ/2x=cos(2kπ+π/2)=1 当x=4kπ+2时，π/2x=2kπ+π sinπ/2x=cos(2kπ+π)=0 当x=4kπ+3时，π/2x=2kπ+3π/2 sinπ/2x=cos(2kπ+3π/2)=-1 当x=4kπ+4时，π/2x=2kπ+2π sinπ/2x=cos(2kπ+