Step repsonse

Hai, I want to plot the step response of the following system. Gp=G1*exp(-s) / [G2+G3*exp(-2s)-G4*exp(-3s)] Can I simply use "step(Gp)" for this. I know that the step command works if we have one term in the denominator. But I am not sure about the above transfer function. Thanks Siva

[newbie traveller]

could you be more specific and detailed???

[Arkadiy Turevskiy]

What are G1, G2, G3, and G4?