原式=tan(π/6-6π)·sin(2π/3-16π)-cos(π/6+6π)·tan(π/6+6π)
=tan(π/6)·sin(2π/3)-cos(π/6)·tan(π/6)
=tan(π/6)·sin(π/3)-cos(π/6)·tan(π/6)
=tan(π/6)·cos(π/6)-cos(π/6)·tan(π/6)
=0