Duality for the G_r,s Quantum Group

The two parameter quantum group G_r,s is generated by five elements, four of which form a Hopf subalgebra isomorphic to GL_q(2), while the fifth generator relates G_r,s to GL_p,q(2). We construct explicitly the dual algebra of G_r,s and show that it is isomorphic to the single parameter deformation of gl(2) + gl(1), with the second parameter appearing in the costructure. We also formulate a differential calculus on G_r,s which provides a realisation of the calculus on GL_p,q(2).