What is the question now??
You could rewrite

as

and be tempted to cancel out the factors of

. But this cancellation is only valid when

.
When

, you end up with the indeterminate form

, which is why

is not a zero.
A rational number is a number that can be written into a fraction. pi, some square roots, e, etc., are irrational numbers(numbers that cannot be written into a fraction).
This deals with exponential growth.
house value = 20,000 * (1.05)^years
(where years is # of years from 1950 - so 1950 = 0, 1951 = 1, etc)
house value = 20,000 * (1.05)^65
house value = 20,000 *
<span>
<span>
<span>
23.8399005592
</span>
</span>
</span>
<span><span><span>house value = 476,798.01</span>
</span> </span>