Question

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

So I know how to do synthetic division and all, but I'm still somehow not coming up with the correct answer! Below is my work so far. Please help me interpret it so that I can get the correct answer. Thank you!

-3 | 1 -2 -4 4
| -3 15 -33
--------------------
| 1 -5 11 -29

I am being told that the answer is 151, but what about the 11 and the -29?

Answer 1

You have a very common mistake.
Notice there is no x^2 term, so you need a 0 as a placeholder

correction:
-3 | 1 -2 0 -4 4
.....| -3 15 -45 147
--------------------
.....| 1 -5 15 -49 151

hard to line up the columns , isn't it ?

Answer 2

Haha yeah it was, I wasn't sure if the spaces would register.
Thank you for this!!

Answer 3

thanks