Synthetic division

[rachelmaddie]

Hi. I need my work checked for this function please.

The given function is f(x) = 5x^5 + 10x^4 + 3x^3 + 8x^2 - 6x - 3
We want to find f(c) when c = 3
This means the remainder when f(x) is divided by x-3
We perform the synthetic division:
5 10 3 8 -6 -3

3| 15 75 234 726 2160
———————————————-
5 25 78 242 720 2157

Therefore, the remainder is 2157.

 

[Deleted member 4993]

Hi. I need my work checked for this function please.
View attachment 20870
The given function is f(x) = 5x^5 + 10x^4 + 3x^3 + 8x^2 - 6x - 3
We want to find f(c) when c = 3
This means the remainder when f(x) is divided by x-3
We perform the synthetic division:
5 10 3 8 -6 -3

3| 15 75 234 726 2160
———————————————-
5 25 78 242 720 2157

Therefore, the remainder is 2157.

You can check "correctness" of your numerical answer by calculating f(3) through substitution of x=3 in given f(x).

 

[R.M.]

I got 2157 as well.

 

[rachelmaddie]

You can check "correctness" of your numerical answer by calculating f(3) through substitution of x=3 in given f(x).

Yes, I get the same exact value.

 

[Steven G]

Hi. I need my work checked for this function please.
View attachment 20870
The given function is f(x) = 5x^5 + 10x^4 + 3x^3 + 8x^2 - 6x - 3
We want to find f(c) when c = 3
This means the remainder when f(x) is divided by x-3
We perform the synthetic division:
5 10 3 8 -6 -3

3| 15 75 234 726 2160
———————————————-
5 25 78 242 720 2157

Therefore, the remainder is 2157.

My biggest problem is that you never answered the question. You were asked to find f(3) using synthetic division. You just did the synthetic division and found the remainder. You need to say that f(3) = 2157 !!!!

 

[rachelmaddie]

My biggest problem is that you never answered the question. You were asked to find f(3) using synthetic division. You just did the synthetic division and found the remainder. You need to say that f(3) = 2157 !!!!

Therefore, f(3) = 2157