Module 4 : Local / Global Maximum / Minimum and  Curve Sketching
Lecture 12 : Curve sketching [Section 12.2]
12.2
Curve sketching
  In this section we shall see how the various tools of calculus developed so far help us to draw a graph of the function . The aim is to get a visualization of the function from is formula . In addition to the various properties that we have analyzed so far some more properties of interest to sketch the graph of a function are the following:

12.2.1
Symmetries:
(i)
A function is symmetric with respect to y-axis if for every in the domain of .
  Such a function is also called an even function. For such a function, one need to draw the graph of only , and reflect the graph about y-axis to get it for .
(ii)
A function is symmetric with respect to origion if for every . Such a function is also
  called an odd function . For such a function also, one need to draw the graph for only. For , its graph is obtained by reflecting against both x-axis and then y-axis.

12.2.2 Examples:
(i)
The function is symmetric about y-axis as .
(ii)
The function is symmetric about origion as
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