Use synthetic division and the Remainder Theorem to evaluate P(c).?

Question

P(x)=2x^3-9x^2-7x+13, c=5

Answer 1

5| 2 -9 -7 13
..... 10 ..5 -10
-----------------
....2 1 ..-2 3

So P(5) = 3

Answer 2

Use synthetic division to divide P(x) by 5
5 |2 -9 -7 13
| 0 10 5 -10
----------------
2 1 -2 3

So P(5) = 3 (Which can be verified with a calculator)

Sorry the columns on the division don't line up better ☺)


Doug

Answer 3

This was answered for someone else not long ago.
Do synthetic division of P(x) by x-5, and see what remainder you get. I'm assuming you've been shown how and can do it. The remainder theorem says that the remainder is equal to P(5).

You can check your answer by substituting 5 for x in the polynomial P(x). If your division and substitution are both right, you'll get the same answer.

Pascal is right, but you could have done it yourself, right?