Which graph represents an even function?
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Answer: last graph
Step-by-step explanation: Graphs of functions that are ODD, are symmetric about the origin.
Graphs of function that are EVEN, are symmetric about y-axis.
We need to figure out which one of the 4 are EVEN. So we take y-axis as the mirror and see both sides, LEFT and RIGHT and see i the points are symmetric or not.
Graph 1, 2, 3 ---- not symmetric about y-axis
Graph 4 ------- Definitely every point to left side of y-axis has a corresponding mirror point to the right of y-axis. So this is an EVEN FUNCTION.