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For this problem we need to remember our difference of cubes
which says a ^3 -, b ^3 factors into A -, B * a ^2 plus AB plus
b ^2.
So in this problem, when I see that s ^3 - 512 and I see the s
^2 - 64, this top is going to turn into s - 8 * s ^2 + 8 S
plus 64.
The bottom is the difference of two squares, so that's s -, 8 *
s + 8.
So the S minus eights are going to cancel, and we get an s ^2 +
8 S plus 64, all divided by s + 8, knowing that S can never
equal 8.
So now, because we're wanting to figure out the continuous
extension, what we're really being asked to do is to figure
out what's the limit as S approaches 8 of that simplified
equation.
So s ^2 + 8, S plus 64 / s + 8.
So when I put in eight, not Infinity, we're going to get 8
^2.
That looks pretty awful.
8 ^2 + 8 * 8 plus 64 all over 8 + 8, so 64 + 64 + 64 / 16.
So 360 fours is going to give us 192.
If we divide that by 16, we're going to get 12.
So the limit as S approaches 8 is 12, and we knew S couldn't be
defined at 8:00.
So we want F of eight to equal 12 to have a continuous
extension.
We have a new definition of a function, so F is usually used
as a capital.
With a continuous extension, F of X is going to equal little F
of X everywhere when X is not equal to 8, and it's going to
equal 12 when X does equal 8.