3x^(1/6)*y^(5/6)÷[(-2x)^(2/3)*y^(1/6)]*[4x^(1/2)*y^(1/3)]=3x^(1/6)*y^(5/6)÷[2^(2/3)*x^(2/3)*y^(1/6)]*[4x^(1/2)*y^(1/3)]=6*2^(1/3)*x^(1/6-2/3+1/2)*y^(5/6-1/6+1/3)=6*2^(1/3)*y.