Prove that 3 is even.
For something to be even the equation f(x)=f(-x) must be true.
Lets say f(x)=3
With that f(x)=f(-x) is 3=3 which is a true statement and our assumption is true, 3 is even.
Lets say f(x)=3
With that f(x)=f(-x) is 3=3 which is a true statement and our assumption is true, 3 is even.