Assignment:
Consider the graph of y = tan x.
(a) How does it show that the tangent of 90 degrees is undefined?
(b) What are other undefined x values?
(c) What is the value of the tangent of angles that are close to 90 degrees (say 89.9 degrees and 90.01 degrees)?
(d) How does the graph show this?
Provide complete and step by step solution for the question and show calculations and use formulas.