Where is the problem? I don't see anything !!!.
Here is how to do number 3:
(-72 - 4x2 + 8x3 - 36x) / (x - 3)
Rearrange the terms in the dividend to be in descending order.
( 8x3 - 4x2 - 36x - 72) / (x - 3)
Now let's write this in long division form.
There are no more terms to bring down, and there is no remainder. So 8x2 + 20x + 24 is the answer.
Very nice Hectictar!
What program did you use to get all that setting out so perfect ?