instead of trying to prove it using mathematical formulas, which may or may not be true due to any number of factors in different scenarious, logically reason your way to a conclusion. Math is logical and can be proved logically very easily, but is harder to prove mathematically, because proving something "with itself" is like trying to say "that's the sun, because it's the sun".
It is the fact that when a number "crosses the border" between having a set number of decimals, i.e. being finite, and having an infinite number of decimals, it is no longer the beforementioned number, it instead "becomes" (or more accurately, it already is) the 'next' number in a 'logical series'.
Though truth to tell I am damn tired right now, and I can't really think straight. What I just said might not apply to series of decimals below .(5)... or maybe even below .(9)...
But I don't really care since this is just 4chan and you'll just troll anyway... so if someone wants to pick up where I left, go ahead.