In two or more complete sentences describe how to determine if the function, f(x)=3cos(x) is even by looking at a graph 25 points & will rate the !

A function is said to be even if its graph is symmetric with respect to the , that is:

Therefore:

SENTENCE 1:Since is symmetric with respect to the , then the function is even as illustrated in the Figure below.
SENTENCE 2:Since , thus , then the function is even as illustrated in the Figure below.