函数g(x)与函数f(x)=-sin(2x+π/6)+1/2关于原点对称
则只需要将x换成-x,y换成-y
即 g(x)=-[-sin(-2x+π/6)+1/2]
g(x)=sin(-2x+π/6)-1/2
=-sin(2x-π/6)-1/2