f(x)=sin(x-π/6)+cosx
=√3/2*sinx-1/2*cosx+cosx
=√3/2*sinx+1/2*cosx
=sin(x+π/6)
(1) f(0)=sinπ/6=1/2
(2) f(a+π/3)=sin(a+π/2)=cosa=1/3
因为a在第四象限,所以sina
f(x)=sin(x-π/6)+cosx
=√3/2*sinx-1/2*cosx+cosx
=√3/2*sinx+1/2*cosx
=sin(x+π/6)
(1) f(0)=sinπ/6=1/2
(2) f(a+π/3)=sin(a+π/2)=cosa=1/3
因为a在第四象限,所以sina