Observe the graph of the function :
The graph represents the parent trigonometric function .
The function is an even function.
Because, .
Thus, the parent trigonometric function shown is even.
Even.
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is an even function.![\"\"](\"/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=5089606f8ee71303999358a9d10f47a5.png\")
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