Question

Use synthetic division to find P(–3) for P(x) = x^4 – 2x^3 – 4x + 4.

Answer 1

Do you know how to do synthetic division?

Answer 2

Well I have just been using a calculator for it because I don't have time to learn, but I got the main idea of it and I just don't know what to divide by in this one. Usually you divide by (x-something) but I don't know what that part is.

Answer 3

Like I would usually use this http://mathportal.org/calculators/polynomials-solvers/synthetic-division-calculator.php but I need the part that I divide by

Answer 4

Err you are supposed to do this on paper. It's pretty easy anyways, so I don't know why you don't have the time to learn synthetic division. You don't use online calculators.

Answer 5

Imagine trying to catch up in two months of school while school is going, yeah that's why I don't have time, could you help me out on this? So if I knew how to do synthetic division I would just divide x^4 – 2x^3 – 4x + 4 by -3?

Answer 6

Hmm hold up

Answer 7

ok

Answer 8

Alright so synthetic division basically is just subtracting the coefficients of the given equation and multiplying it by the factor each time.

Answer 9

So your factor is -3 right?

Answer 10

yeah I guess so

Answer 11

ok I want you to make this on a paper:

Answer 12

See that arrow. Write the equation there instead of the arrow.

Answer 13

k doing it now

Answer 14

now what

Answer 15

oops forgot to tell you, just write the coefficients of the equation rather than the equation. As for the missing x^2 write 0 in that spot.

Answer 16

k got it now what

Answer 17

Now bring the first coefficient down and write it beneath the line. Then multiply that number by -3 and bring it up to the next column. Remember you're subtracting here so take note of those signs.

Answer 18

It will look like this