Consider the graph of $f(x)=\sin(x)$.   

1. Describe the graph.

2. Can this graph be an example of any other function?

   Hint (b):

   What does the graph of $y=\cos(x)$ look like?

3. Explain why $f(x)=\sin(x)$ cannot be a polynomial function.

   Hint (c):

   Polynomial functions are of the form $P(x)=ax^n+bx^{_{n−1}}+...+fx^1+gx^0$.
   How many roots can a polynomial function have?
   How many roots does the sine function have?

   Use the eTool below to examine the graph and to create new graphs.
   Click the link at right for the full version of the eTool: INT3 12-8 HW eTool.