Step 1 :The cosine function is an even function, which means that \(\cos(x) = \cos(-x)\) for all x.
Step 2 :The graph of the cosine function is symmetric with respect to the y-axis, which is the line of symmetry for the graph of the cosine function.
Step 3 :The graph of the cosine function is not symmetric with respect to the x-axis or the origin, because the values of the cosine function do not mirror across the x-axis or the origin.
Step 4 :Therefore, the cosine function is even and its graph is symmetric with respect to the y-axis.