@tomleslie 

thank you so much. I will try to run the code.

@tomleslie 

thank you so much for your response. can you help me plot a graph? Let's say I want to plot a graph for eqn1 with various values of parameter p: p = 0.2, p = 0.5, p = 0.7, p = 0.8. How should I plot it?

@Thomas Richard 

yes, that's what I meant.