#!/usr/bin/env python
# coding: utf-8

# In[24]:


from sympy import init_printing,plot,limit,oo
init_printing(pretty_print=True)
get_ipython().run_line_magic('matplotlib', 'inline')


# In[25]:


from sympy.abc import a,n
from sympy import tan,pi


# In[26]:


expr = n / (4*tan(pi/n))


# In[27]:


expr


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plot(expr, (n,0,1000))


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limit(expr, n, oo)


# In[47]:


expr = n*tan(pi/n)


# In[48]:


limit(expr, n, oo)


# In[59]:


plot(expr, pi, (n,0,5), ylim=(3,5))


# In[51]:


expr


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